Setting up new accounts will not work, either, as you'll be in violation of the T&Cs of just about any room. However, IF any of your current accounts are not already "tagged" to an affiliate, a rakeback site *MIGHT* be able to re-tag your account to them and start paying you; I was able to do this with my Absolute (then VP247) account via a site called RakeSwap, although I'm not sure I'd recommend them . . . but there are many out there, if you just do a Google search. Also, PokerSource just recently announced that any "dormant" Absolute Poker/Ultimatebet accounts are eligible for a re-tag to their rakeback program, but that would only work if you haven't used the account in something like 6 months.
If none of this works for you, as someone already mentioned, you can always set up an account at a new site and get rakeback through them. I recently got one at a new (Everleaf-affiliated) site called SwankPoker, for example, and I'm getting up to 30% rakeback with them, although it's a tiered system, and there's not (yet?) much traffic on the site. Also, I recently contacted Full Tilt in regards to rakeback, and they told me they are working on implementing a program in the near future for existing account who do not yet have rakeback and are not tagged to an affiliate; if you email them about this they'll put you into a database and are supposed to notify you when (or if?) this gets going.