Best commercial handstrap (Updated)

It's not difficult to make your own hand strap for your ereader/tablet, so your hand can relax while reading.
But alternatively, I have found one (count 'em, one) product which is great, in the way I think it should be done. (It should support the hand firmly, but comfortably, and have the thumb free to advance pages on the screen.)

It is the "TFY Padded Hand-Strap plus Velcro Adhesive Patch".

Home page. -- eBay page.

• They also have straps integrated with a light rubber case if you prefer.
• Note: for transport, it folds flat against the tablet. 
• The use for a stand is OK... unless you want to tap too much, because it's not very stable, at least in the portrait orientation. But you can still use the kind of stand which is just a slit, without a back plate. Many of them are great. 

Both the Velcro patch and the strap can be placed where you want them, and removed again.