Having to take part in performances throughout the year, i frequently don a tuxedo. I naturally have my keys with me, and on them I have a Leatherman Micra and a Photon II. Also, I have found it helpful to have a "gentlemens" knife in the EDC rotation. That used to be a Kershaw Chive...until I lost it. I'll prolly pick up another one in the near future. Having a nice knife on the other end of a pocket watch chain is an accepted practice. Lighter is easy...get a nice zippo or something similar. FAK...well, the venerable altoids tin kit works well, and if worse came to worse, your wife could carry that in her purse. Be creative...you generally have lots of pockets in a suit. Just be sure to balance stuff out. It also helps to have a well fitting suit; as I have found out, stuff in the inside pockets show a lot more now that the suit is a little more...shall we say snug.

-Chris