FYI, the Mets are running their Winter Blood Drive this Thursday (tomorrow, 1/5/2012) from 10 a.m. to 5 p.m. at the Caesars Club, located in Citi Field.
Per the Mets PR Dept:
Similar to the Coat Drive and Food Drive, fans donating blood will receive a voucher good for one pair of tickets to a select Mets game in April 2012. Fans donating blood will also receive 15% off regularly priced merchandise at the Mets Team Store with Season Ticket Holders getting 20% off (the discount will be valid on Thursday only).
Fans can enter the ballpark via the Hodges VIP entrance with complimentary parking available in Lot G on 126th Street off Roosevelt.
Complete details are here: Mets Blood Drive