Meet Olly: a small, rather minimalistically designed gadget which is, according to creator Mint Foundry, a 'web connected smelly robot.'  What does this mean?  If sight and sound are already stimulated by the very device with which you are reading this from, then imagine adding smell to this combination.

Your girlfriend/boyfriend messages you on Facebook or Twitter, for example.  Instantly your nasal capacity is filled with the scent of their perfume, due to Olly emitting that individual scent as part of the notification.