The nominated club earns a direct financial benefit per ticket bought and the buyer can choose to be seated with other fans from their club. And Munster and Bath fans hope they are onto winners - on and off the field.
The "League Table" for the ERC initiative has Munster fans just ahead of Bath with Leicester Tigers and Sale Sharks in the chasing pack.
Ospreys fans have put their team at the top of the Welsh regions with Toulouse, Edinburgh Gunners and Rugby Calvisano the leaders from France, Scotland and Italy respectively.
"There is just over two weeks left for Heineken Cup club fans to take advantage of this opportunity to help their clubs and at the same time secure a seat at the Millennium Stadium for the 11th Heineken Cup final," said ERC Chief Executive Derek McGrath.
"We have been delighted with the response so far and its looks like Heineken Cup final tickets will be Christmas presents for many sports fans this year. Cardiff has proved an enormously popular venue for the final on the three previous occasions the club finale has been staged there - there was a tournament record and Millennium Stadium capacity crowd of 74,600 to watch the 2002 final between Leicester Tigers and Munster - and all the signs are the Cardiff 06 final is going to be another well supported European festival of rugby."
To buy follow this link and remember to insert "Blues" as your unique code when buying: