attaching bottles to mixte frame top tubes?
 

Any creative ways of attaching drinks or bags to mixte frame top tubes? -- or special products designed for mixte frames?

For those who don't know, mixtes have thin twin toptubes that slope down from stem to rear wheel dropouts. They also have a joining bar with a large screw hole, that makes for a convenient U-lock holder, but could be useful in much more elaborate carrier systems.

How about a seat mounted or bar mounted holder that takes two bottles?

I second the handlebar mount suggestion (see my various Capo pictures elsewhere). Use two conventional cages and two Minoura adaptors, all readily available at local bike shops.

Not all of them.
the Panasonic mixtie I saw last week had a solid top tube that wishboned around the seat tube.
Top

Most of the mixtes I've seen have the single top tube. Sheldon Brown says it's still a mixte as long as it has triple stays. I prefer the look of the double tubes myself, espcially the pencil-thin tubes on the raleigh Super Course.

I didn't want to put clamps on my wife's mixte, so I gave it a '70s Blackburn rack and a foam insulated rack bag. She can carry water and a bag of grapes. I like to eat grapes when I ride. It's hard to get a drink on the fly, but we're old folks and we take lots of breaks. There's room for sandwiches, too.

http://community.webshots.com/photo/...68014369VNpklt

bungie cord should keep a bottle on pretty good.
Tying a plastic grocery bag to the cross stem would work ok if the stuff inside can be wedged between the 2 tubes.

Although I've seen the single tube that splits into 2 around the seatpost, I would guess its more common for mixtes to have 2 thin tubes the whole length. Seen many more first hand like that.