i've seen a few photos that are similar in the cacti&succulents forum. perhaps they can help if you make a post over there.

I don't know the name but they're a cactus with strap-like cascading leaves. Easy grown from cuttings.

Could be Night Blooming Cereus (Epiphyllum oxypetalum).

Looks like the flower has already bloomed. They don't last very long, but are quite showy when open (in evening and night).

Shame you guys missed that flower, its definatly an orchid cactus, probably an epiphyllum as mentioned.
Filtered light and regular feeding will get you more flowers.

Its a nice lookin plant :D