I've started working on a heavily terrain-based map, which is all new territory for me. Having some problems with it at the moment, if anyone could check it out, I'd be really greatful:
http://twhl.co.za/mapvault_map.php?id=3868
It's going to be very Halo-like, having terrain with structures melding into it, though it will still be to it's very core a Half-Life map with lots of cool interactive map elements like bounce pads, locking doors, and various traps.