[pablissimo]

I currently have open Firefox with four low-image tabs, Word and MSN Messenger. Task Manager's registering around 600 meg of memory committed (bearing in mind that'll also include pages that've been swapped to disk) on a machine with 1gig physical. If I start Azureus, I've just blown another 70meg without even starting a download. More memory => fewer swaps to disk. Disk accesses are around four orders of magnitude slower than memory accesses. That's the equivalent difference of that between 1 second and 3 hours. The assumption of 'buy more RAM' is of course that the amount you have already is inadequate - buying more when you're spare capacity doesn't make sense.

Additionally, you're not taking into account the fact that programmers are now happier eating tonnes of RAM because low-memory-footprint programming is both inefficient economically and largely unnecessary. We as coders have lots of RAM available in general, so we've no qualms using as much as we need. Programs written in .NET (and Java) are, in memory-allocation terms, at the mercy of the garbage collector irrespective of how they're coded.

It'd help to know what applications you tend to run to get a better picture of why your machine is slow, but in general just proper housekeeping will keep things running adequately. Computers don't tend to degrade in performance on their own, but we perceive a difference over time because we're asking them to do more and more things with the same fixed resources they had when we bought them.

Unless you're my step-sister whose insistence on installing every porn dialer and trojan she can get her hands on is the bane of visits home.