Last Night, virtual idol Hatsune Miku appeared on the Late Show with The David Letterman and rocked the house. 

Miku performed " Sharing the World," and the crowd really seemed into it. Dave seemed slightly perplexed.

I first saw this technology applied in person when I was in London watching 'The Lord of the Rings' stage play. The play was horrible but the special-effects were pretty awesome and included a 3-D projection of Bilbo Baggins disappearing in front of our eyes.

Hatsune Miku (初音ミク?), sometimes referred to as Miku Hatsune, is a humanoid persona voiced by a singingsynthesizer application developed by Crypton Future Media, headquartered in Sapporo city. She uses Yamaha Corporation's Vocaloid 2 and Vocaloid 3 singing synthesizing technologies. She also uses Crypton Future Media's Piapro Studio, a singing synthesizer VSTi Plugin. She was the second Vocaloid sold using the Vocaloid 2 engine, and the first Japanese Vocaloid to use the Japanese version of the Vocaloid 2 engine. Her voice is sampled from Japanese voice actress Saki Fujita. Hatsune Miku has performed at her concerts onstage as an animated projection.[1] Hatsune Miku is portrayed to be a 16-year-old girl with long turquoise pigtails. - Wikipedia

Since then, it's been used to bring Michael Jackson back from the dead for a 'live' performance and any number of theme park rides at Disney and Universal Studios.

I wonder how long it will be before a 'Star Trek: The Next Generation' Holodeck is built.