Groupon has a great deal for 53% off tickets to the International Spy Museum. Go HERE purchase your vouchers.
The Fine Print
Expires Mar 23, 2012
Limit 1 per person per visit. If not redeemed by 3/23/12, date of entry subject to availability. Voucher's $10 value may not be used on the following dates: Cherry Blossom, Spring Break, June-August, and Thanksgiving, Christmas, or New Years' weekends and surrounding dates.