best plastic-free children's cup

BPA-free plastic seems to be all the rage these days as the "safe, non leaching alternative".  But a recent study in Environmental Health Perspectives featured in the very informative blog, inhabitots, suggests that even plastics labeled BPA-free could be leaching chemicals with estrogenic activity.  This means that chemicals that mimic the action of the sex-hormone estrogen could be present in our children's food and drink consumed from plastic containers.  Ugh, we though we were doing so well....

We currently use a mixture of glass and plastic bottles for Sam and a few different sippy cups.  It's time for a plastic-free overhaul!

I don't love any of our sippy cups, especially the stainless steel one we have.  After doing a little research, I think I found the sippy for us...for now.  Pura makes stainless steel baby bottles that can be converted to sippy cups and are compatible with many bottle manufacturers' nipples (born free and think baby to name a few) and make their own sippy spout.  They are also completely plastic free!  The only downside I've found so far is that it doesn't have a straw, which I wanted.   I'm thinking I could squeeze a stainless steel straw through the nipple hole...is that a little extreme??  Maybe, but maybe not....

Does anyone else use a plastic-free bottle or sippy they love?