Every MLB team, or more specifically every general manager, has one player on their minds that they would do anything short of liquidating their farm system to acquire.
For a good three years, we saw this with the Boston Red Sox and GM Theo Epstein. Epstein desperately wanted Padres first baseman Adrian Gonzalez, and for years the dream was merely talk. Most people thought that with Kevin Youkilis entrenched at first, Gonzalez would never put on a Red Sox uniform.
However, last offseason, despite the re-emergence of former All-Star Adrian Beltre at third in Boston as well as the surprising relevance of the Padres, Epstein pulled off the trade, sending the system's top prospects to San Diego for the slugging first baseman, subsequently moving Youkilis to third base.
Basically, what I'm trying to say is that even if it looks like that dream trade can't happen, there is always a possibility, because none of us really know what those general managers are thinking.
So what I have done is composed a list of the players that I believe each team is keeping an eye on, just like Epstein did with Gonzalez.
I've based this on the areas each team needs help in, not so much which players are considered "on the market."
After the Gonzalez trade, there are very few players who I can actually see as completely unavailable, as I never thought that after last year the Padres would trade their best hitter.
There may be some repeats, as I'm sure we all know that there are 30 teams and only so many high-quality trade options.