Thri-kreens with a pair of gythka works pretty well, I'd say. 1d10/1d10 double weapons are pretty hot.

DMs letting you run around like Zolo the Swordsman w/ blades coming from every joint is only bringing pain on himself for letting a character roll that many dice on a full attack, especially given how many of them are gonna miss, since most of the weapons mentioned in Kelp's post have inherent penalties to their attack to help ensure that they aren't going to hit, anyways. What I worry about more is if they get the feat Multitasking, which is admittedly difficult to get on a Thri-kreen w/ their Int penalty, but more actions per round is always powerful.