The cactus on the left is a Paper Spine Cactus aka Tephrocactus articulatus var. papyracanthus. It is from Argentina and prefers warmth and good air circulation. The body is shaped like a pinecone and the spines act to keep the body cool. It has lovely crepe-like white flowers. It is easily propagated by removing and rooting one of the "pinecones".
Nice looking specimen.

I'm afraid I don't have any idea what's in the pot with the Portulacaria afra. I'm just here to say that if you don't get an ID here on the tall guy in the pot with the P. afra, it would be a good idea to try GW's Cacti & Succulents forum.

And since I'm saying that, I'll add that P. afra is not a Sedum.

Portulacarias and Sedums are not very closely related: Portulacarias are in the order Caryophyllales and Sedums are in the order Saxifragales. So though both are succulents, they're very distant cousins indeed.

From what I know of them, Portulacarias always have opposite leaves, and Sedums always have alternate leaves.

The one on the right looks like a monstrose form of one of the Cereus spp. I have no idea as to which one.
It is difficult to see from the photo but does it have any spines or areoles ( hairy/woolly pads that the spines grow out of)?

I just wanted to say -- LOL @ your post title. :)