[ProtegeManiac]

  Im just looking for a pair of speakers, that wont need an amp to power them. They need to be able to fit on a desk reasonably. 

That doesn't exist - any speaker requires an amp. Do you have multimedia speakers on your speaker right now? Open it up, it has an amp in there. If it has a subwoofer it's likely built into the subwoofer's enclosure.
 
Maybe what you mean is that there isn't a separate amplifier that will take up extra space on your desk. There are active monitors like the Swans D1010 and D1080, and professional gear like KRK's (this is what I'd use for metal). However, while you might have eliminated the amplifier, you'll still need a preamp to control the volume on these, particularly with the professional monitors, since each cabinet has its own amplifier (so that means two power cables going into your power strip) and also each amplifier has its own gain knob in the rear of the cabinet. Every time you adjust the volume without a separate preamplifier, you'll end up reaching over to the back and counting how many notches it moved from zero to make sure that both speakers are at the same volume level. Hence, you'll still need a preamp - for those who use an interface for recording or a device that has a headphone amp in it as well (if not also a digital to analogue converter), it's not a big problem because it will drive their headphone as well, and they've already eliminated a separate speaker power amplifier on the desk in the process.
 
Non-professional active monitors have a volume knob on the front or the side of the Master unit - which has all amplifiers in its cabinet - then just feeds an amplified signal to its Slave speaker. This is basically a large speaker with a similar hardware configuration to 99% of multimedia 2.0 speakers on computers where signal from the soundcard goes into one speaker and then another cable travels from that one to the other speaker. Those who have wider desks still use a preamp of some kind with these however as the knob on the speakers are likely out of reach since one typically needs to set these farther apart to maximize the stereo imaging.
 
BTW that amp zunehdrocks linked has a surface area that is less than half that of a mousepad, with a height of roughly 1.5inches, so it isn't anywhere near as large as traditional speaker integrated amplifiers (which also come with multiple source inputs, preamp, poweramp direct input, etc etc - all things that aren't needed by computer-based systems).