heh, for unmanaged server, the nest bet is servermatrix, but other companies are fine, as long as you know what your doing, mesing up your server with some dedicated providers shows hidden fee's for rebooting and certain things like that.
We recently got ourselves a VPS for a fairly low-demand application. We were skeptical at first but it seems to be working fine - basically the same as a low-spec dedicated server for around $20/month.