Original Question: I'm wondering how round you can get a 12-inch balloon? Most come out looking kind of egg-shaped. And then there's the knot -- is there any way to push it into the balloon and make it stay?

Funny enough, I was pondering this EXACT same thing today. Here's what I came up with:

1. 11" round balloon, Red 260, two red scraps.
2. Tie a knot in the far end of the 260.
3. With a wooden dowel inserted into the 260, push the 260 into the 11" and, stretching the 11" over the end of the dowel and knot of the 260, tie in place.
4. remove dowel, flip the whole round inside out, Inflate (DO NOT TIE) the 11", Grab the 260 knot through the 11" round (again) and tie in place.
5. Deflate 11", flip right-side out.
6. With the long end of the 260 hanging out of the 11" nozzle, inflate to a round shape.
7. Pull on the 260 to create tension, and tie the nozzle. Snip off excess everything.
- This encourages the round shape and pulls the nozzle into the balloon slightly.

The process described is very similar to Ralph Dewey's (GENIUS!) wobble-Loon technique described here:
http://www.balloonhq.com/column/dewey/jun11/

It dawned on me that the higher up on the nozzle you tied the round the more of an indent you'd get.

Here's a shot of the result when the knot is rolled all the way to the top/end of the nozzle on the round. It sucks the knot way inside. You can stick your finger in there. But I wouldn't