Binokular is your man for that kind of stuff.

I'm not sure thats really possible, or at least advisable! I'm a bit perplexed as to why you'd want to do it? What exactly are you trying to connect the speakers to? Usually each speaker in a stereo setup has a positive (red) and negative (black) connection, these go into the amp (4 connections in total). What speakers usually need to drive them is a power source (i.e. an amp). A stereo mini jack only has connections in total for left and right stereo channels, i.e. no seperate positive/negative connections. Amps normally have phono left/right inputs, if you want to out put something from a source with a stereo jack type connector, the normal way to do this is use a stereo mini-jack to phono adapter, plug the phono leads into the amp, amp outputs to speakers. This is the kind of setup I had for ages with a Sound Blaster live sound card on my PC, then I decided to quit mucking about and get an M-Audio Audiophile 2496 sound card which has proper phono outputs/inputs, plus digital and midi connections too. I still need to use an amp obviously. The only speakers that don't require an amp are powered speakers, these will already have either a stereo jack or phono connectors already.

I'm trying to avoid buying wee speakers for my laptop and mp3 player by putting mini jack ends on a pair of hifi speakers that are lying about. Is is possible/advisable to do this or would I be better off just buying a pair of portable speakers? I've been looking at some of the creative 2.1 selection but if you know anything decent for about €100 I'll give you a big hug and some chocolates. Maybe some flowers if your lucky...

If they are just un-powered hi fi speakers, it won't work, the line out on your sound card simply won't drive your speakers without an amp, so it looks like it'll have to be some portable speakers so. Altenatively, why not just try and pick up a cheap used amp? This would be worth doing if the hi-fi speakers are good quality ones. Just remember not to place the hi-fi speakers too close to your laptop as unlike PC speakers they will probably not be magnetically shielded (PCs don't like strong electromagnetic fields). I can't really reccomend a specific set of speakers, I don't use PC speakers, just run my PC through a Hi-Fi, but Komplett have a wide range of stuff that seems pretty decent, many of them well under €100. I'll pass on the flowers, but you can help me adjust the D2 racing coilovers on my car.

I'll just brush up on my mechanics and it'll be done in a jiffy. Or the next blue moon.