I know this is less programming related and more time management related, but I value the feedback of the users on this site. I\'m finding myself particularly busy this semester
Backpack is a good one from 37signals. They have free accounts, multiple users and an API. I am not sure about SVN access though.
You also might think about TRAC. It plugs in well with SVN, and although is made more for development, it would work well for your needs I think.
Update: You mentioned that Trac is geared towards teams, and while true, I don't think that is really a bad thing. I don't think there are any features in it that really require multiple users or that would slow you down from using it on your own. And if you ever need to collaborate with someone else it will already be set up to do it.