I tried it with a few different push-button switches until I finally found some that were reliable and robust. I currently have one that lives between the Volume and Tone knobs on my Tele switch plate. It's important to know that there are two ways to pull this mod off:
1) A momentary spst switch that is normally closed. Probably the most straightforward idea - you cut the wire going to the output jack, and solder both bits to the opposing terminals on the switch. When you press the button, it cuts the signal. Easy Peasy, CBGB.
2) A momentary spst switch that is normally open. Cut the signal wire going to the output jack and solder both to the same switch terminal. Then, solder the opposing terminal to ground. When you press the button, it immediately grounds everything going to the jack. This is the way mine is currently wired. I think it's a little bit more reliable this way, since with option 1 you might get a DC offset. Most circuits should be able to handle this, I think, but who knows.
Edit: Sho' nuff, the switch I bought was from Tayda:
A-3489