You can use a small amount of isopropyl alcohol on 
a cotton swab (don't soak it, just a little bit) 
and then follow up with plain water to take care 
of any of the alcohol left over.

Be very careful, though.  The alcohol will take 
the paint up immediately.  (If spilled, the paint 
would just run off like water.)

Hope this helps some.  :-)
--Kris
.