While I think a trade of Iggy will be tough to do and get value, here is how the Sixers should approach such talks - focusing on providing the extra value to help solve other teams' problems.  Here is a potential trade:
Orlando Magic get:
Andrew Bynum    Andre Iguodala    Lou Williams      
Magic replace a superstar they are losing, but gain 2 stars and depth that they sorely lack.  They can then dump Arenas' salary via amnesty to free up some cap room.
L.A. Lakers get: Dwight Howard   Jameer Nelson   Andres Nocioni  
Lakers get the best player in the league and another generation of stars to carry on their tradition, since they've already committed to a coaching change and to move away from the triangle offense.
Sixers get: Kobe Bryant  Matt Barnes   Daniel Orton  
Finally the Sixers get a superstar, albeit an aging one.  They sellout games almost immediately and have a tremendous veteran talent to combine with their young nucleus.   Minutes free up for both Thad Young and Evan Turner.

I actually believe this trade provides value to all 3 teams in their current situations.   Would provide some Christmas excitement in Philly, ya think?