Poser with something like a "NET Community Renderfarm" may be a good starting point for CG films with reasonable quality (rendertime: up to 5 minutes per frame) with the length of a song (2 to 3 minutes or round about 5000-6000 frames). Perhaps a way to go for independant music labels with low budget.

5000 frames * 5 minutes = 416 hours rendertime for a single computer (17 days).
416 hours divided by (being optimistic) 50 workstations = 8 hours.
Add some overhead and the film is still rendered within one day.
Or 2 days with only 25 workstations.
Or just half a day if you can hire 100 workstations.
And so on.

Even if 25% of the frames needs dynamic clothing and/or hair (double/tripple rendertime) such a film will be rendered within 2 days (with 50 workstations).

But...

Using dynamics in a renderfarm needs more logic for the software. I think it is possible if the fastest machine computes the dynamics and creates morphs for each frame (hmm - I see a problem with hair). This needs some testing (probably the most complicated part of the software). Seems that this part should be done from the job owner or at least from a trusted workstation (no interupts allowed, if this machine stops working all other machines have to go idle).

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