As one of three National Leaguers on pace for 40+ HRs, JJ Hardy has brought nothing but joy to those teams that drafted him for a $1 or with their last pick or plucked him from the free agent pool right after their draft. The challenge has been deciding what his trade value is.
Every fantasy leaguer, and expert, wrestles with the proper value to assign to a player who is doing things no one expected. The wish of the owners who have this type of player is that the Fantasy Fairy will deliver an owner who will pay for his unexpected production in the hopes that it continues for the remaining 100 games of the season. The reality is a player like JJ Hardy is on everyone's sell-high list and will never get the value of the .300/42/140 shortstop that his numbers prorate to over the entire 2007 season.
Fortunately, JJ Hardy was just traded in my NOKA 124.15 (Nl-Only Keeper league Auction draft 12-team 4x4 15 keepers), and this can be used to get an idea of what his fair value is. Some pertinent information is necessary, though. Hardy was dealt by a bailing team because JJ is out-of-time at season's end. The bailing team got Matt Kemp in return.
In keeper leagues, that minimally places his value at that of a top prospect who is not expected to contribute a lot in 2007 but should in 2008. With that as a basis, you can begin to test hypothetical trades to arrive at a fair value.