Charging the Asus Transformer (Prime) Can you charge the Asus Transformer (or the newer Prime) without the keyboard dock?

Since the tablet itself does not have any USB ports, I don't see how you could charge the tablet without the dock or a very clunky proprietary charging cable. However, It seems insane to manufacture and market a high-end tablet that can't charge without a giant peripheral (and sell/price the thing independently too).

Am I missing something? Or, is Asus just insane?
It comes with an AC adapter and a charging/data cable which can plug directly into the tablet, though it does still use their proprietary cable connection since it plugs into the same connector that the keyboard dock uses (the other end is male USB). 

Using proprietary charging cables is not unheard of - Samsung and Apple have done this; I don't personally like it when companies use proprietary cables, but in this case it's mostly because the charging/data port doubles as the dock connector.

Here's an image from Engadget's unboxing/review of the Prime. The AC adapter is at the bottom.