I'm going to divert my attention from why the Texans should trade Sage Rosenfels to examine the flip side of that coin--what teams should be calling the Texans inquiring about Sage Rosenfels, particularly in light of Sage's comments in today's paper.  A quick list of the teams I believe for which Sage would appear to be a marked upgrade as a starting (not second-string) QB:

1.  Baltimore--I realize the Ravens probably don't want to add a thirty (30) year old to their stable of QBs, but wouldn't Rosenfels represent an improvement over what they currently feature?  And trading for him would leave them free to use that No. 8 pick to address their offensive or defensive lines.
2.  Chicago--you're telling me Sage isn't a better option than Rex Grossman and Kyle Orton?
3.  Minnesota--we're waiting by the phone like an ugly girl the night before prom, Twin Cities.  Sweeten that pot!
4.  Atlanta--it's only fair.  You gave us a QB last spring; time for us to return the favor.  You can afford to part with a second-round draft pick this year anyway.  Stop being so greedy.
5.  Carolina--I don't care what people say; I'd be worried about Jake Delhomme bouncing back.  And don't forget the success you've had "rehabilitating" former Houston signal-callers!  It's win-win, baby!
6.  Miami--this only really makes sense if Parcells thinks John Beck can eventually earn the job and wants someone to hold down the starting gig for a season while the second-year player soaks it all in.  Unfortunately, I think Parcells is more likely to make out with Bill Belichick than he is to give up a high draft pick for veteran help in 2008.
7.  New York Jets--you'd think they'd be happy with their tandem of Chad Pennington and Kellen Clemens, and you're probably right (though I think a good argument can be made that Sage is better than both of them).  But given the way they've spent money like it grows on trees since free agency began, it's clear they are living for the moment.  Trading a second-rounder (or a third and something else) shouldn't be out of the question, should it?
8.  Kansas City--if they bring back Damon Huard, adding Sage wouldn't make much sense.  But is Sage a superior option to Brodie Croyle and/or Tyler Thigpen?  Methinks so.