And projectpath.com (among other choices) for the actual Basecamp account. It doesn't even have the name in it! But it doesn't need to.
Having the commonly used name isn't always a great idea anyway. You might want to avoid python.com (NSFW), for example. But the Python folks could have easily gotten codepython./com|net|org/
Your ideal domain + an extra short common word at the end of it: tip, now, it, ify, zone, space, net, repeat word + .com