What's a good, cloud-based project management tool for a small group?
I am on the planning committee for a small, annual convention, and we need a way to organize all the tasks that must be considered and accomplished for each year's event. We want to be able to identify a task, categorize it, give it a deadline, and assign it to a committee member. We imagine something cloud-based (and preferably free) would help the six of us coordinate amongst ourselves (we are scattered throughout the country). But we're not familiar with project management software, and left to our own devices, we'd probably resort to using something lame, like a Google Docs spreadsheet or a wiki.
My hosting provider offers one-click installations of dotProject, but I haven't yet investigated exactly how it or others might suit our needs. Both Basecamp and Wunderkit have been recommended, but I haven't yet delved into either. Can you recommend some further options that are worth experimenting with?