To work on a small project does not need to use complex systems to bugtracking.

Keeping it simple (stupid ;).

Within minutes I’d set up a basic spreadsheet that covered off all the key things you’d want to know if you were tracking bugs.

Here is what I got : Simple issue tracker template.

Google Docs is a free online system that is designed for collaboration works.
Using your  Google Account, you can quickly create and publish issue to either an invite  to everyone who has the link.

Total cost? Zero, apart from my time which was approximately 10 minutes.

You want even more easy to use? Use the form.
Create a form in a Google Docs spreadsheet and send it out to anyone with an email address. They won’t need to sign in, and they can respond directly from the email message or from an automatically generated web page. Creating the form is easy: start with a spreadsheet to get the form, or start by creating the form and you’ll get the spreadsheet automatically. Responses are automatically added to your spreadsheet.

More Google Docs issue tacker templates.