I can put pitlocks on the skewers and the seatpost, but what do you guys do to keep the seat from getting stolen? Cable lock? Is that sufficient? I have a short ride to the train coming up in a couple of days (moving to house near commuter rail), and want to ride to the train, but one bike has a brooks I really like, and the other bike has my aliante, which I can't stand to replace $ wise.

Cable lock? BB nail polished into the bolt head on the seatpost? Any ideas welcome.

I used an old bicycle chain and chained it to the seatstays to protect from theft. I also put it inside an old bicycle tube to protect the paint on my bike. It looks crappy but it works. To steal my seat you need a chain tool.

You can get Pitlocks for the seat bolt too. My husband just uses a cable through the saddle rails to secure his.

Can you use a QR and take the saddle with you?

Folding bike and take it on the train with you?

Perhaps a less Precious saddle? ugly saddle cover? Wally world Bike?

With a Plain type seat post , a slip off clamp can be made,
borrowing parts made for Bromptons by them.

then the Post stays and the rain and stuff won't go down the seat tube.

cable lock made for skis

Buy an extra cheap seatpost and seat, and a cable lock. The less valuable, the less likely they will make an attempt. The cable lock is needed, because if it's cheap but easy to steal, they will take it. I had a cheap seatpost and seat stolen.

Or a pair of pliers, or side cutters, or big screwdriver - to name a few other things that can break a chain.

The perp only needs a chain tool if he plans on reconnecting the chain.

If I had a really nice seat, I'd take a picture of me sitting on it butt naked, and hang it off the seat when you lock it up.

You would keep your seat, and get a pervert admirer.

This is what I wrote to a similar post:

Unfortunately you never know when a crime is going to happen to your bike. I personally had a Brooks stolen and now realize there were a few things I could have done differently.

1) Replaced the quick release as soon as possible (my bolt on had broken and I had a QR lying around)
2) Replace the bolt with some kind of locking bolt like the Pitlock
3) Keep the saddle covered with some kind of plastic bag
4) Lock the saddle rails to the seatstays using an old bike chain or cable.

Basically the saddle and seatpost would be safe using three different deterrents.

I use a thick 7' cable in conjunction with a good u-lock. I loop it around the seat, through both wheels and onto the lock. It's kind of a pain each time, but it's pretty good security and a lot cheaper than a full pitlock set. If I were worried about the area I was locking my bike up I might also use my saddle rain cover to hide the fact that it's a Brooks.

I've seen people use those skinny 2' cables too. Loop it through the seat, wrap it around the seat post and lock it somewhere to your frame or rear rack.
I see this on a lot of bikes but I always thought it's a bad idea (no offense). It's not hard to break a chain, and if you're protecting a Brooks or other desirable saddle, the type of person who would steal it for themselves would have access to a chain tool. Especially since so many other cyclists use the same method.

I like the seat cover idea. Use a pink color shower cap covering your seat and that may just might keep macho theives away from your Brooks.