Well, if you liked MoR, there are the two other Big Rationalist Fanfics:

• http://www.fimfiction.net/story/62074/friendship-is-optimal (don't judge it because it's about ponies - it's really good even if you dont like them) (if yo like it, don't forget to check out the meta-fanfics)
• http://luminous.elcenia.com/story.shtml (as good as the thing it's parodying is terrible)

Also in a similar style: http://www.sagaofsoul.com/

Then there's the scifi classics, if you're willing to shell out some money. no links for these. Here are a few good ones to get you started

• Permutation City
• Accelerando
• Diaspora
• Fire Upon the Deep

This should be enough to get you started. I can give you MUCH more if you want to and maybe tell me some other things you like. Finding stuff like this to specification is basically what I do.