Proporta offers an entire range of "BeachBuoy" cases for smartphones, tablets and e-readers.
They are 100% watertight up to five meters, so you can be sure your precious gadget will stay safe.
Cost: From $19.95

Otterbox's option for Kindle Fire is not 100% waterproof, but it does boast three layers of protection (including a screen protector, polycarbonate shell and silicone skin) so you'll be protected against drops, dust and sand.
Cost: $69.95

Kindle Keyboard owners should check out Speck's BookShield, which is tailor-made to fit the third-gen gadget, protecting it from impact, dust and dirt — although, not water.
Cost: $39.95

Another generic option that fits most e-reader brands, this case will protect gadgets from water, sand and dust.
Cost: $23 from Amazon

TrendyDigital also offers an entire line of waterproof cases suitable for Kindles, Nooks and more.
Available in different colors, there is also a version with a built-in headphone adapter, if you'd like to listen to your e-reader, too.
Cost: From $15.99

Waterproof to one meter, this pouch will fit some Kindle, Sony Reader, iRex, Bookeen and Cool-er e-readers. Its flexible design means it's easy to roll up until you need it.
Cost: £14.99 (approx $23)

Another ruffty-tuffy option for the Fire, the Drop Tech Series is ideal for clumsy types — just don't drop it in the pool.
Cost: $49.95

Guaranteed submersible to an impressive six meters, OverBoard's robust offering will fit any slimline gadget measuring up to eight inches-long and six inches-wide.
Cost: $39.95

A zip-lock bag also works really well. I usually tape it so it is tight around the screen of my kindle to get a good view. Works great in the bath spa or pool for occasional splashes and wet hands.
What about iPad?
I brought my Sony Reader to the beach without a cover and the screen freaked and started doing random actions on its own. The repair tip is to use a business card and run it under the bezel and above the screen to pull out tiny gains of sand. Do it a couple times gently to make sure you get all the sand grains out.