I use a paper towel substrate. And the tank's not that big, anyway, I was thinking of moving her soon to a larger one (and more secure, if I ever get her back). She's definitely not in her tank, or anywhere nearby it. She's now been gone about 48 hours and no sign. There are holes in my room which lead to roofspace and floorboards and such, so I'm very concerned, and I can't dismantle my house (it's not even my house, actually).
I've had three bottles in the upstairs part of the house, with inverted tops and warm slit fuzzies inside, but she hasn't taken the bait yet. Could she have travelled downstairs? I didn't think that she'd have been inclined to, and it's gonna widen the search significantly if she's down there. >:-(
Any more suggestions or tricks? She's about a foot and a half long and only a few centimetres wide, so she could be anywhere in the house.