I have a Microsoft X6 sidewinder keyboard, it's pretty awesome, keys could be a little bigger, but the ability to take of the number pad, is awesome for desk space.
The mouse I use is a Saitek Cyborg, the mouse itself is ugly, and the resize function is rather useless, I also had some trouble with the software and it wouldn't let me bind any keys, but that's where it's awesome, it's got about 8 free buttons that I often bind numbers for weapons/spells, and also C for when I'm playing L4D2 I can use it to talk.
 
I think it makes a big difference really, I wouldn't say I've noticed a change in skill, but I like using them alot more.

I use a Logitech MX Revolution / 5500 Bluetooth Mouse and Keyboard combo.  Fantastic range and works on almost any surface.   I do this because I also use a 32" 1080p LCD TV  as my monitor in my loungeroom.  That said, I think that wired mice don't compare to wireless for hardcore gamers.

I use an old G11 and an MX518. Love them but bought them when the price was slightly lower.
 
The MX518 is especially good

I don't but wouldn't mind purchasing something. Then again, I just got a new PC and have been on a PC gamin hiatus for about 2 years so, give me some time....

Changing or charging your batteries every 3 months is too much work for you? Do you just throw out cellphones when the battery is dead so you dont have to charge it? "

" I'm using a Microsoft Reclusa keyboard (apparently made by Razer), which I bought mainly for the backlight. It's meant to be a gaming keyboard, I think; there's extra buttons on it for media player shortcuts which are really handy. I guess they intend you to assign various tasks to these keys in game but I don't need 'em. I'm also using a Microsoft Intellimouse Explorer 3.0. I guess this was a premium mouse in it's day. "

i use a custom built mac keyboard with leds in it for gaming at 5 in the morning and i use a blue tooth mic for my head set

o ya the keyboard is wireless