Among the more unconventional ideas for eliminating debris are foamy "nerf balls" or panels made of aerogel, shown here.
A man-made, super-light solid, aerogel was used as the capture medium in the Mir Environmental Effects Payload
(MEEP) Orbital Debris Collector, to capture debris particles over 18 months in 2009. Its porous properties and low density make it an ideal candidate for picking up debris before being rocketed back to Earth--much like putting a layer of Jell-O on your windshield to catch bugs.
The downside? Aerogel can only be used for small debris--paint chips, metal slag and dust--most of which aren't a big threat to large spacecraft.