What do you use for bug/issue tracking of your private projects?

Currently I'm using an Excel sheet for keeping track of bugs and change requests for my Visual Studio Add-in GhostDoc. The worksheet was easy to set up and definitely does its job -- for now. But I'm not sure how things work out in a couple of weeks or months.

Searching for "bug tracking freeware" on Google, there doesn't actually seem to be a shortage of tools I could try, given an infinite amount of time (which I don't have). So I'm asking the bloggers out there who have their little private pet project running for some time now: How do you keep track of things? I would definitely prefer something that doesn't require a web server.