Brake caliper stuck

On my way into work today my front passenger side brake caliper locked up.
Is there anything I can do to unstick it so I can limp the 9 miles home?

Give it a chance to cool down, I supposed by now that should have happened. Then drive it carefully home. I would try to avoid braking real hard. I've had this happen on my vehicles (more than one including my XJ), when they have sat a while.

You could take the cheap way out and pull the piston out of the caliper. Hone the cylinder and replace the seal and dust boot. Phenolic calipers tend to do this, in my experience especially if they are older. When phenolic calipers were originally used, somewhere in the late 70's early 80's, the phenolic would swell. They used to sell metal replacement pistons. Or you can just replace the caliper.

Mine did that, I had to release the pressure on the bleeder. Still don't know why it wouldn't release.

Thanks guys.
I jacked it up and spun the tire. It turned pretty freely. so I limped it home without incident. I'll tear into it when I get a chance.
I have no idea what happened. I guess it just felt a little unloved.

Mine locks up all the time. Pretty sure in my case its a bad brake hose though.

You're right on the money big Jim. That's what happened in my case.