They won't help you if you've got a cold, but Kleenex's new antiviral tissues should help prevent you from spreading it. Kleenex claims the tissues, treated with citric acid and sodium lauryl sulfate, will kill 99.9% of cold and 'flu viruses.
(Credit: paeyl, a Hoopy Frood Who Really Knows Where His Towel[1] Is.)
[1] And his Kleenex.