[d503]

Web Intents (which should be in Chrome soon, or maybe they're in already) should hopefully allow exactly that.

http://webintents.org/

Latest news seems to be on G+: https://plus.google.com/u/0/116171619992010691739/posts

[groby_b]

It's definitely in :)

Grab a Canary build, start playing with it right now.