Ivy is toxic to pets, but if your cat doesn't bother with your other plants, and if he doesn't get into something because it's "new"(like my cats do), then you can probably get away with it. I have lots of houseplants, but I removed almost all of the ones that were deemed toxic when we got a kitten. I did, however, keep some Heart-leaf Philodendron(also toxic), which I keep in small pots on a shelf above my kitchen sink. The cats just don't go there. There are other plants they have access to, if only to knock them over when they're bored. I also grow wheat grass for them. I have other vines in wall pockets that are not harmful...Hoya, Tradescantia/Wandering Jew(which they like to bite pieces off of and bat them around the floor), and Swedish Ivy. But I love my little Philos, so I keep them trimmed and out of reach. HTH

Here is a link that might be useful: ASPCA

Yeah, I knew it was toxic already.

Are there any non-toxic climbers that come to mind? I think the cat wouldn't be dumb enough to try to get to the ivy, and I can certainly arrange for it to not be near him. Just a bit concerned that this is an accident waiting to happen.

Two that are on the ASPCA non-toxic list are Swedish Ivy and Grape Ivy. Hoya(Wax Plant)is safe and gets long, but is very slow growing(on the plus side, it will eventually reward you with flowers). I have a Swedish Ivy, but it doesn't travel very far in my rather dark apartment. I read that Grape Ivy gets pretty long and might suit your needs/wants. You might also ask in the Houseplant Forum for more suggestions. If you check the ASPSA's list, you will see that some plants are on both the toxic and non-toxic lists, as some plants are toxic to some animals and not to others.

Here is a link that might be useful: non-toxic plants