Tacky Tape is effective as an air conditioning duct sealant, body sealant, and temporary adhesive. It's for sealing the panels of metal buildings (roof & wall), but it's also used for temporarily hanging things on walls (like posters). So it can sometimes be found with school supplies, or in the attics of metal buildings, or at metal building suppliers.
http://tacky-tape.com/products/butyl-sealants/sm5227/ 
