Themes for use with Mutlisite help

I have a multisite network set up and am in the process of picking themes to use.

I now we have theme options available here at WPMU (farms 133, Nelo, etc) but wonder which other themes are being used.

I have checked out Edublogs and it seems they have their "default" theme and offer the themes in the farms pack.

I would like to use some other themes on my network to give my end user some different options.

Does anyone know of themes with a developer license that allows you to use for client work in this manner?

Thanks in advance!