Really, that's all I need to know.
It's a large-ish slot about the size of a PCI slot.
What are they used for?
I haven't heard of them before, and i'm looking at two mobos, one of which has a DPS slot and no other features added above the other, but is $60 more. Is this mysterious DPS slot going to be up-and-coming new technology that i'll be smacking myself for not dishing out $60 on?
250 points if you can explain it to me, and tell me what they're most frequently used for. I'll make it 300 if you find me a website with such an explanation and pictures. I like pictures.