Um..Ergo Proxy is really good, um High School of the Dead is pretty awesome but has a lot of fan service and some questionable parts. Plus it has zombies...
eno..Pani Poni Dash is really funny and random, or Natsume Yuujinchou is very awesome, followed by Zoku Natsume Yuujinchou(Second season). Those are the only one I can think to say right now...they aren't really well known...