Good question!
I've found one tactic is regularly effective in situations like these (cable providers, credit card companies, etc.): just call 'em and ask them to waive the annual fee/lower the interest rate to something more reasonable. If you're in good standing, they're usually receptive to the ol', "Hey, yeah, I'm just gonna close the account and move on" proposal." No need to be annoyed or angry with 'em... just be matter-of-fact. Lots of companies respond reasonably to such calls.
If that doesn't work, I'd propose something perhaps a little more unconventional: just pay the cards down and close the accounts. Yeah, your credit score will take a hit, but if you're not going to make a big purchase these next 12 - 24 months, the money you save may make it worth the short-term score set-back.
Thoughts? Any other suggestions from the Turbo community?