Have you ever tried to input more than one word using a remote control? Frustrating, right? From search fields to account info, ditching the remote control for a real keyboard has undeniable merits, especially if you're using a wireless model...
Apple Wireless Keyboard
Using bluetooth technology, the Apple Wireless Keyboard is an exercise of minimalistic proportions. Yes, you will be missing the numeric pad on the side and you will still need some kind of mouse or trackpad for the rest of the inputs but the design and size are a big plus on this small keyboard. Bluetooth on this keyboard has a long range (we've been able to use it up to 30 feet!) and batteries last a long time. Price is around $69
Miyoshi Ultra Thin Wireless Keyboard
Very thin and it feels very luxurious. It weighs only 850 grams and uses the 2.4GHz wireless spectrum for long range connectivity. It has some specific hot keys that works with most applications. The built-in touch pad means that you have to buy one less input device, since it's already attached to the keyboard.
KeySonic KSK-3201 RF Super Mini
The KeySonic multimedia keyboard has brushed metal finish with built-in 7 mm optical trackball, and two mouse buttons. The folks at KeySonic implemented 2.4 GHz wireless connectivity to ensure maximum responsiveness and it also features the X-Type membrane technology which enables extremely silent strokes (no more waking up your love one sleeping next to you!). 12 multimedia keys: Pairing, Play/ Pause, Stop, Backward, Forward, Media player, Mail, Internet, Mute, Volume up, Volume down and Sleep mode. The KeySonic KSK-3201 RF is only available in Europe for a retail price of 37 Euro.
Other wireless alternatives are:
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I use the Logitech PS3 http://amzn.com/B000W5RBQE which works great. I only have one minor gripe, and that you can't disable the tap-click on the track pad. Otherwise is basically perfect.
Two very inexpensive ones that I have used recently and found perfect for couch control:
HP Mini Keyboard http://amzn.com/B004WK3G50
Very small, not for large amounts of typing, but good for HTPC and occasional surfing. Has a unique touch controller for the mouse
Logitech K400
http://amzn.com/B005DKZTMG
Slightly smaller than standard size with touchpad.
I'm using Lenovo mini wireless keyboard w trackball. Model is N5901. It's a handheld keyboard smaller than my ps3 game controller. I like it better than most half size keyboard w touchpad combo for it's small size. The only down side might be the ease of typing.