This is likely to be mostly bottom-feeding, but occasionally there will be an unrecognized gem.
To my mind, these three players might be worth a flyer, if they are non-tendered:
Wade Miller, who was non-tendered a year ago by the Astros due to injury. He was just fair for the Red Sox last year, but maybe the second year back from injury be better. He is only 29.
Junior Spivey, who was also hurt last year (twice), and who never has done quite as well as his .301/.389/.476 first full ML year (2002). If Todd Walker is dealt, he'd be a far better 2B option than Neifi, though. He also seems the sort of player that Dusty Baker would love.
Kyle Lohse, an inning-eater who has apparently worn out his welcome in Minnesota. He is 27, doesn't walk people (although last year, he didn't strike out many, either), and if the Cubs acquired him and he succeeded, it would at least be some payback for the horrendous Rick Aguilera deal in which he was given to the Twins in 1999.
Also, it has been reported by the Denver Post that the Cubs have told the Rockies that they are "keeping" Todd Wellemeyer, for whom the Rockies had been at one time interested in dealing. Since Wellemeyer is out of options, some think that means that Wellemeyer is guaranteed a 2006 bullpen slot. It could, however, simply mean that the Rockies don't have anything the Cubs want; or it could mean that they have something going to deal him somewhere else.
Have at it!