Might be a mistake, but people are ordering the large-tall(36x18x24) exo-terra for 25.99. Petco CAN cancel the order and change it if they want, but it doesn't hurt to try if you really want.
Just thought I would let everyone know!
edit; And the error has been fixed, it's up to 259.99 on sale. Wep!
Probably a mistake that they won't let anyone take advantage of, but it has to ship by freight anyways, which will probably make it not a good deal with shipping costs alone.
I'm not sure how much it would cost with shipping-someone mentioned elsewhere if buying multiples to buy them separately because of the shipping costs, but it would still cost less then the terrarium on regular price.