Y'know... with all of the similarities between Windows XP and Mac OS, it amazes me that Microsoft has never figured out that it might be helpful to be able to see the size of a folder in Windows Explorer. Sure, you can right click on the folder and get its properties but that's more clicks than I care to make and comparing the size of two folders is... well, it's annoying.

Enter Folder Size, a nice bit of open source goodness that simply adds a "Folder Size" column to your Windows Explorer windows. One less annoyance.