From the Tokyo's Best Stuff
The Metropolitan Art Space
A huge cavernous building with possibly the most dramatic escalator ride on earth. I've never found the art that inspiring, but heck, that elevator is worth a visit! in West Ikebukuro on the Tobu side, across from the open plaza.
Hundreds of bars
The area north of OIOI plays host to hundreds of bars and clubs, shops and restaurants, pretty much around the clock.
Certainly the world's ultimate camera store, at least 5 levels of photographic equipment from the classic to the ultra-modern. North east of the station near the Mitsukoshi department store.
Tokyo tends to be a largely low-rise city, so the 60-floor Sunshine 60 building definitely stands out. Walking a few minutes west from Ikebukuro Station you can't miss it (aparently it is on the site of an old jail. Don't miss the free express elevator, which is renowned as one of the world's fastest elevator rides (230 metres in half a minute). You can get your ride from the basement.
Toyota's main showroom is in front of the Sunshine 60 centre (the building is clad in blue metal). If you show a valid license it's possible to book for a drive of a modern Toyota around the internal track.
Aquarium & Planetarium
On the 10th floor of the Prince Hotel building, adjacent to Sunshine 60.
A handyperson's paradise, you can buy anything you might need to build almost everything at this awesome retail experiment. In the main street (name escapes me).