Best known in New York for the two-and-a-half seasons he spent with the Yankees from 2006 through 2008, Kyle Farnsworth has been a major league relief pitcher since 1999. Those three years in the Bronx certainly didn't go well for him, as he posted a 4.54 ERA and 4.73 FIP, though those numbers weren't quite as bad in the high-scoring context of those seasons as they would be today.
Entering his age-38 season, Farnsworth has had a decent career, hovering around league average in most years but occasionally putting together a very good or very bad campaign. He didn't fare well in 2013 as he made 39 appearances for the Rays and another 9 for the Pirates with a 4.70 ERA and 4.14 FIP in total. He wasn't much better in 2012 for the Rays, but he had one of his better seasons in the big leagues in 2011.
Three years removed from that season, Farnsworth would not make for an exciting signing, though his value figures to be pretty low. While he doesn't look quite as good as LaTroy Hawkins did last winter, perhaps he'd make for a similar type of signing for the Mets, who are still looking to bring in a relief pitcher, per Sandy Alderson's comments to Adam Rubin.
Like Hawkins, Farnsworth now throws a couple of miles per hour slower than he did in the past, though he still averaged 92.6 miles per hour on his fastball in 2013. If Farnsworth would be willing to sign a minor league deal, the Mets wouldn't stand to lose much by bringing him on board. According to Zach Links of MLB Trade Rumors, several teams are interested in Farnsworth.