Is it bad that I lost a screw inside my computer?

Today I took my old Sony laptop apart for the first time to see what was inside. In doing so I dropped a small screw into it and it rolled under something, and now it won’t come out. The screw was not very important (I think), but I’m wondering what the chances are that it could harm whatever it landed on. I dropped it between the hard drive and the CD-ROM. My guess is that it’s sitting on the motherboard, or the modem, or the sound card, or something similar.

Now I know that I could disassemble the entire computer, but I don’t feel like doing that, so I am asking you people instead. Could this be a problem?

And I am sorry if this is a stupid question. I’m a software guy, OK?

Worst case it shorts out something, makes a big puff of smoke, and flames shoot out of the door of your CD-ROM. I’d go in after it, or at least do some vigorous shaking to see if I could get the little bugger to work its way back out.

I have witnessed the toasting of a motherboard by someone (stupidly) trying to put in the screw that holds one of those card-slot-blank things (that fill up an empty PCI slot) while the machine was running. He dropped the screw on the motherboard and it went tick and never turned on again. Advice seconded.

Yikes! Thirded - you need to get that screw out of there. If you don’t have one ask a computer geeky friend if they have a tool - looks kinda like a syringe and 3 small wires come out the end. Could help if you can see the screw but can’t reach it otherwise. Looks like this
Uh page 2 scroll down to #5 - chip/parts retriever.

You need to get it out, but disassembling laptops is a pain. Lots of snap fits and little parts that go ping! and spring out all over the place.

Take the battery out first - the screw can’t do any harm if there’s no power. Then take out everything modular that is easily removable. Then shake the laptop and see if you can get the screw to drop out, or at least rattle so you get an idea where it is. Shine a flashlight through the gaps left by your drives, poke it with a straightened paper clip, buy, borrow or steal a magnetic screwdriver and give that a go. Basically, elect for keyhole surgery before full dismantling.

OK, after some further disassembly and long flashlight-accompanied gazes I found it and worked it out. It was kind of lodged between the end of the motherboard and a piece of metal.

Thanks folks.