I think it would be a productive move to trade Lidge. Closers get way too much on the market and Purpura should take advantage. There are plenty of instances of relative nobodies stepping into a closer's role (Turnbow, T. Jones, Fuentes, etc), and I think Wheeler or Qualls could fill it with relative success, while improving the club. There has to be at least one team out there that will overpay for Lidge, like Toronto overpayed for Ryan and the Mets overpayed for Billy Wags. Here are some possiblities that could work.
To Baltimore with a package for Tejada. (Unlikely)
To Atlanta for McCann, Joey Devine, and maybe another prospect.
To Texas for Frank Fransico, Kevin Mench, and possibly a prospect (Cordero may be in way)
To Milwauke for either Capuano or Doug Davis
and Dan Kolb
To Philly for Pat Burell and a prospect
To Cleavland with Adam Everett for Johnny Peralta and maybe a prospect.
To Chicago White Sox for Garland
To Chicago Cubs for Angel Guzman and Cory Patterson
out.