Tokyo Sightseeing Art

Sensor-based interactive art... That's a tall order. I don't have any real recommendations for it. "Chiyoda Arts 3331" (http://www.3331.jp/en/) next to Akihabara is not very interactive but quite artsy.

Apart from Akihabara, I definitely recommend spending a day in Odaiba, a tourist spot located on a reclaimed-land island in Tokyo Bay. There's a lot to do there: One neat way to get to Odaiba is to take the Water Bus after spending the morning touring the old temple at Asakusa. If you're lucky (well, lucky if you like anime) you might get the "Himiko". https://en.wikipedia.org/wiki/Tokyo_Cruise_Ship
 * the Miraikan museum has some good science
 * the Panasonic showroom used to have a "house of the future." Might still.
 * the full-size Gundam and G-Front
 * on the interactive side, the Venus Fort shopping mall has a "real-time" lit ceiling
 * the ferris wheel and the Fuji TV observatory are OK

For weekend spots I recommend being prepared for Sunday, which is when school is out and places will be crowded. If you like fashion or people-watching, the cool places to go would be:
 * Harajuku / Yoyogi Park where you can see cosplayers and rockabilly
 * Shibuya for young fashion
 * Akihabara (traffic on the central Chuo-doori street is closed to cars on Sunday)

Other artsy places:
 * the Mori Arts Center in the Roppongi Hills complex (which is close to the Roppongi nightlife spot but not too interesting otherwise)
 * 21_21 Design Sight at Tokyo Midtown (also near Roppongi)

You might (depending on your battery life/wifi) also want to spend some time with the recommendations from reddit: http://www.reddit.com/r/japan/comments/bvxaw/rjapan_information_hub/

Also: try the yakiniku and yakitori. Unless you're vegetarian.