The service has four business plans (ranging from $20 to $175 a month), and an individual plan that is free (though limited). The top two plans offer SSL and significantly more storage space for documents. All plans support web timers (to track how long you spend on a given project), but you can also enter time manually if you hate working to a clock.
Intervals is offering a 30-day trial on it's business plans, and they don't ask for payment info until after your trial (so they won't do the devious automatic billing without you being well aware of what you're getting in to).
