I did a PacMan I'm pretty happy with. I'm wearing a PacMan maze suit/tie, and made a paper mache Pac Man head to go with it. Yellow shoes, socks, and gloves, and a PacMan belt buckle. I then used a Wav Trigger sound board, portable speaker, and rigged up some wiring to miniature buttons in my glove. Snaked the cabling from the glove up my sleeve with a Cat-5 cable that I could disconnect to keep the glove and the rest of the system in my inner suit pockets separate for managability.
When I pressed my first finger and thumb together, I made the wakka wakka sound. When I pressed the second finger, the PacMan death sound. The third finger played PacMan fever. The fourth finger had volume up and down buttons.
I topped it off with a glowing, color changing ghost about a foot off my body via a transparent PVC pipe, with styrofoam balls to represent maze dots on the pipe, illuminated from within with blue LEDs to give them a bit of a glow.
The whole effect was a 3D PacMan costume with lights and sound. Was pretty happy with the results and got lots of photos.
Starting with a brief video: