Very cool article on techcrunch about How To Build A Web App in Four Days For $10,000. It's actually more interesting in the way of viewing what tools are suggested and the idea of taking a break for the grind of work to do something quick and creative to re-invigorate a development team.
I remember doing this once long long ago while working in the basement of the company-that-was-Netmaster... at some point or another the boss (that'd be now-windows-security-expert Dana for those not familiar with my work history) got into a discussion with someone on some mailing list and we ended up taking the afternoon off to build a web portal. It never actually went anywhere, but it was fun, fast, and a good mental exercise to get the juices going again. I recall doing this again years later in the company that Netmaster morphed into to create a three factor authentication addon for our security product, but it was far more stressed, more work, less fun, and that it never went anywhere was kinda a pissoff cause it was a really cool system. Ah well, live and learn :)