IK Multimedia's Modo Bass physically models bass guitars.
This isn't exactly a competitor to Pianoteq and its technology, but it is an interesting development. I wonder if this product will be successful.
http://www.ikmultimedia.com/products/modobass/
"Enter MODO BASS — the industry’s first true physically modeled instrument from the leader in analog modeling technology. 8 years in the making and developed in collaboration with one of Europe’s oldest universities, MODO BASS is a completely new breed of instrument..."
