I was thinking on making it all GPL, and sell services/support, so that enterprises could use it internally or externally on GPLed software, but when they needed to build closed source external software, they'd buy a license.

There is a problem with GPL though: we cannot sell licenses if we merge in other contributors code, because we wouldn't have the copyright to license that under another license other than GPL. That wouldn't be a problem if we never accept contributions.

We could also sell support, consulting, build up entire software solutions... the problem then is time. At this moment there is only me and a friend in the project.