These clusters of joy are called Cereus Peruvianus but also Cereus Repandus or Peruvian Apple Cactus. The curious thing about these fellows is that they apparently also produce edible fruit that can grow up to 4 cm long.
There are some studies that suggest these plants also reduce the amount of harmful radiation and static electricity produced by TV and computer screen. We're not 100% convinced on that front but it can't hurt to have a pretty like this on the desk, right?
These comes from the desert so make sure they're in a sunny spot, in well-drained soil and try to keep from touching them too much (ha!). They do need water but not very often and none at all over winter.
Materials: Live plant in cactus soil in a plastic pot
Dimensions: Height of the plants varies but is at least 22 cm