First - what you're thinking of doing, and have done in the past, isn't cloaking never mind double-cloaking.
http://support.google.com/webmasters...n&answer=66355
Sounds more like a "doorway page" to me, though.
What you are doing is risking being penalised for
duplicate content, as by the sound of it you have multiple websites with the same content. The changing the colours tactic - do you
really think Google are that dumb?
The best thing to do with multiple domains is: -
1) Point them each to different websites. And I mean different. or
2) Point them all to the same website (parked), but with a 301 redirect for any not matching your main domain. A 301 redirect tells search engines the page they had indexed has "moved permanently" and to index the new page instead. Essentially this means that all except your main domain will be indexed - the only reason you have the domains is to stop competitors using them or to catch traffic in the case of ex-competitors. You can use them on literature if you like but they will never be indexed by search engines.