What is a 1 x PCI-E x 1 slot used for?

[TimBlanchard]

I noticed a lot of motherboards have these, what are they used for?

[joshd]

umm i think some network adapters use them, and maybe some SATA controller cards etc, but they are not really used that much at the moment.

i think the plan is that they will become used in the future, as an alternative to PCI.

[Apokalipse]

Ageia PhysX cards will use them, as well as 4X slots..

[CrazeD]

I think there are some sound devices that use them, I'm not sure what though. I'm thinking something MIDI, but I dunno.