The server portion runs on anything that can run a PHP enabled web server.

The client portion runs on pretty much anything remotely modern.

I have no pi so I can't say how well it actually runs.

The Pi is fairly limited in terms for resources. I was wondering if it could support OwnCloud with its low end hardware. I attempted to run OwnCloud on 128m of ram and ran into a lot of problems.

This would be why I never bothered owning a pi.

I tried it but it was very slow.

no it doesn't.