All of the normal disclaimers apply here: I am a core member of the dotProject team and have been for 3+ years in addition to using it for quite a while prior to that.

Update:  As of April 2008, nearly all operations have been moved away from Basecamp in favor of Highrise, also from 37signals.

One of the questions I get most often is:

Which is better: dotProject or Basecamp?

Well, to be honest with you... neither. I believe that although they're both called "project management tools", they have fundamentally difference uses, strengths, and weaknesses. And I use both regularly and on a daily basis.

Since Basecamp is the visiting team here, I'll look at it first: