I've been looking for a while for kobo glo slim covers (the type with the molded back) and a few weeks ago, settled for a tuff-luv slim case. the annoying thing is that it covers the power button so I have to use my nails to slide the power button T_T
otherwise it's very feminine and I really like the design and it feels quite thin but nicely padded. Although in the pic it looks like it might slide off the cover at any moment, it's actually quite secure because the elastics are tight and not very stretchy.
http://www.ebay.com.au/itm/380453882...84.m1439.l2649
Then today, I found this:
http://www.aliexpress.com/item/Smart...937476755.html 

FINALLY a CHEAP slim cover with auto sleep/wake function

It looks like the kindle paperwhite one and there's a magnetic closure... I'm not sure whether the magnet is placed in the correct area though?