So you have a nice playlist growing in your iTunes library, but what happens when you're out on the road and all you have with you is your mobile phone? nuTsie is here to help.

nuTsie is a music client that streams in your iTunes library. Well, as our friends at EngadgetMobile have pointed out, the nuTsie system actually reads the names of your tracks and matches them to whats on nuTsie's server. With this in mind, your main computer does not have to be left on, and the nuTsie application does not require you to upload music anywhere. All you have to do to get started is upload your iTunes Library.xml file to nuTsie's server under your account.

Performance for this service is said to be pretty good, with extremely good connection speeds. Just watch out when you close your clamshell phone, some have been reported to shut the nuTsie applications right off. The service is free to use during the public beta period, but the list of compatible mobile devices is pretty slim at the moment.

One of the things that technology should be able to help us with is to figure out what we really want, and give it to us. While that may sound like a tall order when you think about the entirety of it, when applied to specific scenarios, it makes sense. For example, Amazon can give you some pretty good ideas about books you might like to read based on your previous buying habits.

Along with book selection, another area that is ripe for picking with respect to automated selection is in the generation of music playlists. And while it's easy to have iTunes to create a playlist consisting of your favorite music, it's not so easy to have it automatically create a playlist of music that suits your mood, be it melancholy, neutral, or ecstatic.

If this is something you've wished was easier to do, check out Moody. Moody is a little utility that allows you to tag your songs very quickly and easily based a two dimensional grid of 16 squares. You simply choose the square that best represents the mood of the song you are listening to. The y axis of the grid represents the intensity of the music, from calm at the bottom to intense at the top. The x axis represents the emotion of the music, from sad at the left to happy at the right. Each axis has 4 possible positions, for a total of 16 squares.

You can tag songs as you listen normally, or turn on a QuickTag mode which will start playing each song from a position you choose (say, 40 seconds into the song), and jump to the next song as soon as you make a mood selection. This allows you to tag a lot of music very quickly.

While at first it can seem overly simplistic to try to pick one square that best represents a song, the choice of 16 squares appears to be a perfect amount to cover the majority of your music. The playlists that you can then generate using Moody are quite consistent in terms of the mood of the music, since you were the one that decided how that music made you feel. It can be very comforting to be able to choose a selection of music that suits your current frame of mind, without having to think too much about it.

Moody is a free Mac download, and one that we are happy to heartily recommend. We just wish it had a square for snarky blogging music.

The Filter boasts quite a lot. Its tagline is "creates perfect playlists from your iTunes library," and its web site says it's "better than your shuffle button!" What The Filter is is a plugin for iTunes (Windows version only for now, Mac coming soon) that generates playlists when you select a few songs and click on the big black "F" button. Like many programs, The Filter claims to excel at building playlists based on your mood. I gave The Filter a try and found that it's actually not too shabby. I selected a few songs that I thought would go well together in a playlist and it filled out the rest of the playlist with songs that fit in pretty well. While not every one was one that I would have picked myself, none of them seemed out of place, and after all, The Filter touts its ability to help you rediscover music that you'd all but forgotten you had. Like Pandora and other services, The Filter learns from your listening habits and tweaks your playlist based on which tracks you skip and which ones you listen to all the way through. I've tried a number of products that claim to do what The Filter does, but most of them either didn't work very well or were far too complex. The Filter is the first one that really seems both smart enough and simple enough to really give a shot.

I used MoodLogic for awhile to create playlists tailored to my moods, and it performed pretty well, but I wasn't really satisfied with the limitations of the free version. MusicIP Mixer is a free Windows app in the same vein. You choose a song from your collection and it will generate a playlist of songs that it deems similar. While you can start generating playlists as soon as it's installed, the initial algorithm, though fast, seemed wanting to me, and the subsequent (and presumably more accurate) algorithm takes a long time to analyze your songs. It does have some nice features, though, like integration with other players so you send generated playlists to Winamp or iTunes, and compatability with portable devices. It also has a built-in music-recommender that will query the web for new music you might like. Though I haven't been using it long enough to really judge the quality of its algorithms, MusicIP Mixer has a nice polished feel and is worth checking out if you're sick of assembling playlists by hand.

[Thanks, Tim!]

As in everything else, the blogosphere is well ahead of the media-at-large when it comes ot music, so the best way to stay on the cutting edge of music (or at least appear that way) is to watch the music blogs. It turns out they're chock-full of great MP3s, but if you're like me you don't have much time for reading music blogs and downloading song files. Enter the Hype Machine, a music blog aggregator. It watches all of the best music blogs and gives you their MP3s in easy-to-digest formats: Podcast, .m3u playlist, or a pop-up Flash player for listening in your browser. I'm partial to the Flash player because it has links to the original blog posts as well as albums for purchase at Amazon.com. There's also a handy search feature, so the next time a friend tells you, "You've got to check out Avant Garde Dark Cabaret Harmonium Quintet of Love!" there's a good chance you find some of their tracks as well as some informative blog commentary.

Our pal Todd Carter over at PVR Wire points us to TiViTunes, a nice little Windows app that lets you access your iTunes playlists from your PC-connected TiVo. It works by shuffling the playlists around on your hard drive so they're somewhere TiVo Desktop can see them. It's shareware, so until you pay $5 it's limited to the first five songs in each playlist.

Thanks, Todd!

Sometimes we want to let the whole world know what we're up to. I mean everything. We have blogs, webcams, chat rooms, and tons of other things to let us communicate with people. A lot of people take pride in what music they listen to and like to share it with others. Whether for just the public eye or to see if anyone else likes the same kind of music, you still need a way of getting it on the web easily. iTunes Publisher does just that. Currently at 4.3.3, it's a great little program that let's you export your iTunes library in a number of ways. You can customize it by font and look, what columns you want shown (Artist, Album, Song, etc.), and how you want your data exported. The best way is probably via a webpage. It's listed nice and neat with tables so that everyone can just scroll away. Plus it's one file and you can easily upload it and update it anywhere. I highly reccomend checking it out if sharing your musical tastes with the world is your sorta thing.