I wanted to try my hand at a geometric styled necklace. My lovely wife graciously modeled it for me: wouldn't fit around my neck :-P
Modeled in Maya. Had no overhang issues, all angles are 45 deg, minimal cleanup: Just the 'spiderwebby' PLA hairs.
Spray-painted it two tone: Black and red, it's reversible.
Printed with "natural" PLA on Makerbot Replicator. "Medium" print setting defaults in Makerware: 1 extra shell, 10% infill, 215 deg extrusion, HBP off.
No raft was needed, but your print platform needs to be spot on for the initial layer to stick.
51 minute to print.