There's another solution that works, but is even less practical. Get a soundcard with optical input. Connect one end of the optical cable to the console and the other end to the soundcard's optical in. Connect the speakers to the soundcard analogue out. The sound will be output to the speakers using the sound card. Like I mentioned, it does work, but this is hardly a good solution because:

1. You need to buy the soundcard, which won't be cheap (X-fi Platinum or similar)
2. The PC needs to be turned on while playing
3. Can't use this setup when connecting to a television set (unless the PC is dragged to the TV)

This brings us back to the most proper solution: buying the decoder. I've been contemplating buying it from 2003-2005. But I found myself resisting because of the high asking price. In the end, I just settled buying a Logitech Z680. This ended up being my gaming setup until now. I can't say whether the price of the decoder is worth it, but it really is the most proper solution to your issue.

for those who havent got the spk,why not consider a basic HT which come with everything including 5 spkd and subwoofer? Or else get a USED AVR amplifier( below RM1k? ) which can convert analog signal and convert it to Dolby Surround.Anyway,if getting a AVR,i think it should come with optical input,so just connect the console with a optical cable could be good. 

i think u guy can settle for this OLD baby
found them from my under stairs..since now using X-Fi fatality

U have to power up ur PC when playing PS3/Xbox360...  
Power to be on:
1)PC
2)PS3/Xbox360
3)speaker

wow! can post more pic of it, need more details on that..does it hv the green, black, orange inputs? is it for sell,????? 

lksing, it looks like that sound card process sound by it's own. can we just modified the power so that we dont need pc to be turned on? or it still need pc to operate it?

how are you going to connect to ur xbox. i dont see any optic or normal input. just AUX input available there. for a dvd player yes it have AUX output. but not for xbox.

i think u can connect through cable that is given by the PDVD-9208, which is the red, white av plug converter that is link to the green black orange plug n connect it to the decoder. then u plug in ur pc speakers plug to the decoder...and some how magically true surround sound will come out?...otherwise some one can comment on this?

i'm afraid that thing won't produce 5.1 sound from the ps3(not sure about other consoles).surround sound for the ps3 is hardware restricted meaning 5.1 can only be produced using optical connection.the cheapest solution i think is to use Creative HQ-2300D Headphone.the bundled decoder can decodes dolby digital,dts and dolby pro logic II.and best of all it accepts optical input.the downside?battery powered,but i think it can be modifed to be usb-powered.i myself haven't tried it but i think it'll serve the purpose of producing true 5.1 sound from your ps3 to your pc speakers.

edit:there's a thread in garage sales selling the headphone http://forum.lowyat.net/topic/707288

i'm using a sony set that set me back Rm999 two years ago. Nothing fancy but you do get very decent 5.1 sound when gaming, but not as punchy as some of the 'computer' speakers from creative. you can say it is more refined, and definitely kicks arse when watching movies (for a cheapo sub 1k unit, that is)