You can get large bags of silica gel for less than £7 on Amazon in the UK, not sure about elsewhere, but they work a treat. Prevention rather than cure is always a better way (I know it's a bit late).
I love these :) Make a great wall display.
The Polaris deck is doing something similar for a reward...
http://www.kickstarter.com/projects/goldklangdesign/polaris-new-deck-from-vanda-playing-cards-printed?ref=live
Whilst I agree everyone is entitled to their opinion - saying that they shouldn't be able to use Kickstarter because it's not "breath-taking" is a little harsh IMO. What is a stunning design to one person is something completely different to another and is not fair at all on the guys who put in...