ISO Large Playmat (similar to base of activity mat)

[srhs]

ISO Large Playmat (similar to base of activity mat)
Does such a thing exist? DS is rolling and moving all over and is off the activity mat in no time (or is caught on one of the crossbars).
If I just put a blanket down, he grabs hold of it and pulls it over himself.
I like the base of our activity mat and would just like THAT, only larger. If it had fun texture things to play with, all the better.
I don't want one of those big foam areas.
I found this Baby Genius: Cuddle Pals Play Mat (http://www.amazon.com/Baby-Genius-Cuddle-Pals-Play/dp/B000T9RTPG) and it's 3x3'.
Anyone know of anything larger/better? I really want it to lay nice and flat like the activity mat structure...just BIG.
TIA!

[LBW]

Alex Toys makes one. Costco was selling them for $35 a couple of years ago, but they sold out quickly and haven't returned.
http://www.walmart.com/catalog/product.do?product_id=9224823
It's a nice, thich mat, and folds in thirds to about the size of a crib mattress.

I've also seen gym mats at educational supply stores, so you could try there.