The list of ex-coaches sitting on the sidelines this year is awfully long, awfully talented, and will likely cast a lengthy shadow upon the entire NFL this year and into the next off-season.  It's generally accepted any more that there will be signficant coach turnover in the NFL.  Every year, websites and bloggers discuss which coaches are on the 'hot seat' and speculate that without a stellar season, that coach will lose his job.  With the cadre of talent on the sidelines, I would think that some owners will look long and hard at the talent patrolling the sidelines of his (losing) team, and the list of coaches waiting for a call, and pick up the phone - both to fire the current guy and inquire about the other guy.

Mike Shanahan.  In what was perhaps the most surprising termination, Shanahan got the boot after his Broncos imploded last year, losing 3 straight games to lose the division and lose out on the chance at the playoffs.  That implosion was laid at Shanahan's feet - he couldn't coach his guys to a win (or motivate them) and his GM duties were being questioned more and more each and every year.  Denver had a great offense under Shanny, but that defense was woeful, and seemed to get worse each year. 

There's no doubt that Shanahan could immediately provide a boost to a struggling franchise.  He's seen as an offensive wizard, and his body of work certainly supports that.  Yet, an owner looking at Shanahan will have to deal with that ego, and his desire to run the entire ship.  Some owners won't like that, and so the list of owners that would give Shanny a hard look are probably slimmer.  That doesn't mean he won't soon be an NFL coach.  Shanahan will likely be one of the first guys called by an owner looking to stabilize the franchise.  Working out the details won't take too long; Shanahan himself is on record saying he wants to return to the NFL one day.

Mike Holmgren.  Holmgren has said that he needs a break, needs a chance to step away from the game for a while.  But most people expect him to one day come back; once he rests, relaxes and rebuilds the energy necessary to coach, he'll likely get a long, hard look.  Holmgren has a lengthy body of work that is virtually all positive.  He's won a Super Bowl, appeared in another one, and has done wonders with teams like Seattle.  For the Seahawks to become nationally relevant is perhaps the most impressive feat of his career. 

Holmgren, like Shanny, will probably want more control over the football operations.  Again, that's a tough nut to crack, but in Holmgren's case, I think that if he was working with the right sort of GM, the partnership would work well.  Holmgren, like Shanahan, is an offensive minded coach, and will want a certain type of player on his team to get the most out of his offense.

Jon Gruden.  Gruden's firing came at a surprising time, but I don't think that it was much of a surprise overall.  He's been wearing thin in Tampa, and perhaps the chance was necessary.  Gruden brings an intense, fiery personality to the sidelines, and while he may be difficult to relate to (among other coaches and his players) that doesn't mean he's a good coach.  He knows how to get the most of his players, and puts them into a position to win.  Had Oakland (re: Al Davis) been a little wiser, perhaps that franchise might not have fallen upon their current hard times.  Gruden was the kind of coach that could stand up to Davis (perhaps the reason for his firing, then) and gotten production.  His pass-heavy offense is a tough one to defense.

Gruden may or may not return.  He may find TV work easier, more fun, and better for him than returning to the sidelines.  But I think that his personality won't let him stay away from the sidelines too long.  Listen to him carefully on MNF this year - the criticisms he levels may indicate whether the burn to coach is still there.  I would think the first time he says 'well, this is what I would have done' you have a signal that Gruden is thinking ahead.

Tony Dungy.  Of the ex-coaches, Dungy is the only one in which the chances of him returning are virtually zero.  Still, one never knows - it might take a quiet conversation or the perfect situation.  My guess with Dungy is that if he returns to football, it will be either in an advisory position or as a GM.  I think he'd make a terrific GM, by the way.  But, as I said, the chances of him returning are less than 1%.  But he's out there, and I'm sure that inquiries will delicately come his way from time to time.

Bill Cowher.  Now, Cowher is the only really defensive minded coach that's out there, and he too has stated that he wants to return to the game.  But in Cowher's case, I think that he's going to be very careful about it.  It will take possibly more money than any of the previously mentioned coaches; rumor has it Cowher wants no less than $8 million a year to coach, and one thinks he'll demand $10 a year.  He's a difficult, stubborn man to deal with because in all things its his way or no way.  But, he's easily the best motivator of the group, and relates extremely well to his players.  Cowher most likely won't end up in the AFC North - no matter how many rumors swirl about Cleveland - because he'll see it as a betrayal to the Rooneys.  Even though he was upset with them regarding his contract, it's obvious that he's not all that interested in crossing swords with them.

Personally, I think that Cowher will likely be lured to a southern team, and perhaps next year.  If I were John Fox or Jack Del Rio, I'd be worried a little about my job.  The Carolina job would be almost tailor-made for Cowher; he's moved to Carolina, obviously put down roots there, would not face the Steelers except once every three years (or potentially in the Super Bowl) and the Panthers are already built along the lines of Cowher's liking. 

Speculation is wonderful, and of course no one knows exactly what's going to happen.  All four of these coaches will be sought out - and Dungy will get some questions, too - by various owners who want to get back to winning ways.  I wouldn't surprise me one bit to see one or more of these guys back in the league in 2010 or 2011.  It really wouldn't.  The thing is that all of these guys have solid track records, have won Super Bowls, have dealt with Super Bowl pressure and expectations, and have generally all been highly successful head coaches.  Those facts alone virtually guarantee that they will get a job at some point.  One things for sure - the 'hot seat' for coaches is made all that hotter because these guys aren't currently working.  The constant discussion regarding troubled coaches will quickly rise to the level of a roar because of these talents waiting in the wings.