I don't want to sound too whiney, but I told them about my Mbox tool (which merges Mboxes into one single DB file) and they said 'Send a resume', then said I didn't have enough experience, even though the tool was the basis of the job offer.

It seems mean to me, to offer someone a job and then withdraw it because I'm not a 9-to-5'er with a job. In fact, it sounds pretty IBM-ish.