Saw this on one of the bargain sites I frequent and thought some may have a use …
http://www.under-tec.com/store.php
Under-Tec.com offers its new UnderEase Undergarment with Flatulence Filter for $24.95. With $4 for shipping. Available in sizes XS to XXL, these “unique” undergarments feature a replaceable flatulence filter that, well, filters flatulence :o . Complete the customer satisfaction survey to get an additional filter for free. Of note, the older Gas Eaters Undergarments, with a non-replaceable filter, are $11.95.