What USB DACs are available today and...

What USB DACs are available today and what large, Mac-compatible external hard drives are quiet and fast? I used to have the Wavelength Audio Cosecant, but sold it due to non-use. But I've been ripping more and more CDs lately and would like to consider another, less expensive USB audio set up. Thanks.
TwinDac Plus
many other cheaper alternatives like the bithead and computer mfg offerings....

You don't need a fast hard drive for music...I'm using an 80g Toshiba notebook drive per Gordon Rankin. It's not the cheapest route to go, but it's quiet ( I can't hear it at all) and it's not powered by AC.

Check Gordon's web site...he know's what he's doing an d offers plenty of free advice...it's working for me.