I have purchased 25 Tubes of RNAstable (http://www.biomatrica.com/) products 93221-001 and dessicant pouches 14001-007. You can dry your RNA and send it across the world at room temp. Rachel has carried this out successfully by sending to Russia for one particular application and Anja was keen to try also. Can also be used for long term storage of RNA (without need of risky -80′s). It’s about £6 per sample- cheaper than sending on dry ice.
Of course check that it is OK for your own application (contact the service provider) and discuss with your supervisor before diving in. Cheers, Andy.