I bought the Trek SOHO commuter cup. I had to order it from the Trek dealer, but it is specifically designed for bike bottle cages. It is plastic lined, but has a stainless outershell. It is pretty leak proof (not totally leak proof, but I have to shake it to get drips to come out when closed) and fits the bill for me. It keeps the drink warm while on the commute and for a few hours after (not as good at maintaining warmth as my vacuum bottle, but not a fragile either). It is supposed to be standard equipment with Trek's SOHO commuter bike (hence the SOHO name), but my dealer had never gotten the bike or seen the cup. I had them special order it and was surprised as the cost was only $9.99 when they rang it up (YMMV as it seems way better quality for the price they charged and the ID number stated it was 14 oz when it says it is 18 oz on the cup). I may have gotten a bargain, hence I bought 2 at that price.