Well, Whadya Know

The world's biggest pair of panties, made from acrylic and lace, measured 29.4 ft. (8.97 m.) x 14 ft. (4.26 m.)? They were strung across London's Oxford street as part of a promotion.

[source: GuinnessWorldRecords.com]

A promotion for what? Or is that one of those questions I don't really want to know the answer to...