I remembered a couple of weeks ago someone saying they wanted a Gaptech... one just appeared for sale on eBay...
http://www.ebay.co.uk/itm/Bmw-Z4-E8...in_3&hash=item20cb74221a&_uhb=1#ht_500wt_1413
http://www.ebay.co.uk/itm/Bmw-Z4-E8...in_3&hash=item20cb74221a&_uhb=1#ht_500wt_1413