1 Iki Piki: So, how does the ship's new supercomputer work?
1 Spanners: Oh, it's really quite clever.
2 Spanners: It uses time travel technology to steal CPU cycles from computers in the past.
3 Spanners: With so many underutilised computers in the past, we have almost limitless computing power!
4 Iki Piki: Don't people notice their computers slowing down?
4 Spanners: Nah, they just think it's Windows.

2012-09-29 Rerun commentary: I've always been very pleased with this idea I came up with - that highly advanced computers can achieve their staggering processing power simply by hijacking idle CPU cycles from computers that existed in the past. After all, the vast majority of computers spend almost the entire time they're switched on doing pretty much nothing, with the CPU running over 90% idle.

Some projects such as SETI@home, Folding@Home, and now many others as well allow people to opt in to a distributed computing project that makes positive use of the free processor time on their computers. This is great, but the drawback is that it's opt-in! There are still millions of computers out there sitting idle most of the time. If only there was some way to tap into that potential!

Yes, I realise botnets essentially do this sort of thing: take over CPU cycles from unsuspecting computers. But a botnet does this for evil. What if you could do it for good? What if you could make use of that idle CPU time for something worthy, and do it in such a way that (a) nobody notices, and (b) there are no negative effects on the utilised computers? (Again, I realise that "no negative effects" might actually be impossible in practice, since you'll at the very least be using more power - but bear with me, okay?)

And what if you could combine this with time travel in such a way that you only use CPU cycles from computers that were idle in the past? You don't steal processing time from computers now - you only ever take it from computers, say, at least 12 months in the past. Ones that have already been used without the owner noticing anything untoward.

Brilliant!

Anyway, we all know time travel technology won't be invented until some time in the future. At which point all of our CPU cycles will be fair game.

Now you know why your computer seems to run so slow sometimes. Obviously they still need to iron some of the bugs out of this system.