I have a handful of (content unrelated) sites with decent PRs and I'm considering hosting them all on the same server. I've heard that if you do this, internal linking between two seperate domains on that server may be seen as less "valid" by Google in PageRank terms (since you obviously own both of the sites as they share an IP address).

Anyone have any experience in this? I'd love to save some hosting cash by consolidating, but not at the expense of losing the ability to link my sites together powerfully.