Couldn't invest in some portable saddle racks and take all your stuff home? I would never leave my gear in an area where I knew many people had access to it. I absolutely HATE my stuff being used by other people because it's invariably my nice gear and always gets wrecked... I would rather, if something is going to be damaged, that it's me and one of MY horses that's to blame!
Otherwise I guess your only option is to make or buy a nice big lockable box and pour concrete in the bottom so it can't be moved easily... or padlock it to something immovable, with a lock designed to prevent it being cut.
The only thing I would EVER leave easily accessible in a public area (boarders only tack room or otherwise) is halter/lead so my horse could be caught and handled easily in the event of an emergency. Preferably a halter and lead that look ratty but are still safe and strong. I use rope halters and my leads are tied on rather than clipped. I have written my name and my horses' names on both my leads.
If you absolutely cannot take your gear home or lock all of it up I would suggest nameplates for your saddle/s and halter/s and tags for your bridle/s and reins. You can get lightweight and strong little keyring tags that can be connected, via a small keyring, to basically any buckle, ring or loop on any bridle or rein (or pair of reins), and you can remove them for shows, but they remove any excuse for ignorance.
Otherwise go the way pleasure riders around here go and spraypaint/permanent marker your name onto EVERYTHING.
Far as I'm concerned your BO should not be using any of your gear or any other boarder's gear without prior consent. No person should be sent to get gear who does not know which gear is the BO's and which gear belongs to boarders. And if anything is lost or damaged because the BO has used it, then it should be replaced.
I had a BO tell me basically the same in reverse... I was welcome to use her facilities (did not board there - she is truly lovely though, one of the rare gems who will gladly lend out her arenas and jumps to anyone who wants to use them) but if I broke anything I was to pay to replace it. I wasn't to touch anybody else's horses and I wasn't to touch any gear that was not mine, or part of the arenas or jumps - and if I changed anything I was to put it back the way I found it when I left.
My mother borrows my gear sometimes and it drives me mad so I know how you feel! I have told her she is welcome to it as long as she leaves it how she found it, in the place where I left it and adjusted how I left it. The exception is my show gear, nobody except me is allowed to touch my good gear. I keep that at the house rather than in the shed where all my everyday stuff is.
Last edited by blue eyed pony; 11-08-2011 at 05:15 AM.