I never used it, but it sure looks interesting if your application doesn't fit GAE anymore or you want to make specific infrastructural adjustments. They support multiple different database/http/.. servers too.
This project looks promising. Could be a good basis for a consulting business, taking apps that have hit some obstacles or design limitations on Google AE, and getting them running on TyphoonAE-based hosting with app-specific infrastructure customizations.
I never used it, but it sure looks interesting if your application doesn't fit GAE anymore or you want to make specific infrastructural adjustments. They support multiple different database/http/.. servers too.