Specialized now sells a premium bike tube that comes in a zip-loc bag and is prepared with talc. The MSRP is $4 more than the regular, bagless and talc-less tube, and I can't find any other difference.
I got some cheap half-sandwich-size zip-loc bags and some talc, squeezed all of the air out of the tube and folded it into the bag, shook in a dash or two of talc, and squeezed as much air out of the bag as I could when I was zipping it up. (As a bow to friend Dave C, this is a tube that I've rescued and patched.)
(The talc really does make the tube sit in the tire better, and makes the tire a smidge easier to change.)