I was informed that this is a big scale temple style flea market. I was planning to visit the market this sunday. If anyone else is interested on antiques or just about any random collection i think this is a good place to look.

OEDO Antique Market
Date and Time	The first and third Sunday of every month. (Date and time is subject to change) 9:00 a.m. - 4:00 p.m. The event will be held even when it rains lightly. It could be cancelled due to heavy rain. One can make sure by checking Organizer's Website: http://www.antique-market.jp/eng/index.shtml
Venue	Courtyard of the Tokyo International Forum, 3-5-1 Marunouchi, Chiyoda-ku, Tokyo.
Transportation	JR : One-minute walk from Yurakucho Station or five-minute walk from Tokyo Station (The basement can be accessed via a concourse from the Keiyo Line at Tokyo Station). Tokyo Metro: The basement can be accessed via a concourse from Yurakucho metro station.
Admission	Free
The number of dealers	More than 250 licensed antique dealers.
Organizer	The OEDO Antique Market Executive Committee
Special Cooperation	Tokyo International Forum

Here is the website for that market. Never been there myself, but it looks promising.

http://www.antique-market.jp/eng/index.shtml

awesome thanks for posting. It is officially on my list!