"Personal lubes" are either:
"water based" -- Astroglide, and most other common lubes (including "Wet", I think)(they usually have lots of glycerin);
"silicone-based" -- "Gun Oil", "KY Intrigue", etc -- largely in sex shops (look for "siloxane" or "dimethicone").
[There are also hybrid products, which I haven't tried.]
They both seem to work for "enhancing" lather.
Charles
PS -- there's even a Wikipedia article !!!!!! --
http://en.wikipedia.org/wiki/Personal_lubricant