What do folks use to clean cables/connections?

I like Kontak. It's pricey...like $40 a bottle...but I can hear a difference.

Good luck.

I use the Caig de-oxit cleaner and contact fluid I bought from Music Direct.

I like the Caig De-Oxit for step one. Step two can be the silver goop, or Caig Gold or even the Cardas connector juice. Lately I've been mixing the Gold and the silver stuff to thin it out and apply it very lightly with a foam (as opposed to cotton swab).

The other thing I do I learned from Pierre at Mapleshade. He sells an anti-static device called the Iconoclast. Though I bought it to use with CDs, I always zap cable ends with it as well.

Grain Alcohol (if it's good enough for NASA, it works for me) and Detoxit.
Don't drink the Detoxit please,

Denatured alcohol has always been a good metal cleaner, (And optics cleaner also) is easily gotten, and might be a good product for step one. Naturally for cleaning connections-binding posts etc, I don't think one would have to resort to HPLC grade to get the job done.
One could then perhaps finish up with Caig Pro Gold? Mark