The only Frank's I've found in Beijing was stolen from a restaurant table, and I don't even remember which restaurant. I bought a big-ass bottle when I was visiting family for Thanksgiving, I fear it may run out before long though :-/
Willy waggling aside I really like the chili dogs at Dogs on Fire in The Village. The chili isn't like what I've had before, it's crunchy! Nice warmth though - it clears you out but without any unpleasant raw burn.