I've always known about the existence of Gundam 0079 Card Builder but never knew what it actually was until I went to an arcade recently.
Located on the 7th floor in a Shibuya arcade, two sets of Gundam Card Builder machines took up half of the room - a set of machines consist of a huge screen so that by-standers could watch the battle and 8 machines where people sit at - pictures at the official site.