It's almost dizzying to look back even at the past ten years to see how much the tools we use to make electronic music have changed. The wealth of technology has given us more tools to create with than ever before, but it's created something else, too - an almost endless cycle of trying to keep up with the latest and greatest. Even those of us who have been doing this long enough to know better have probably found ourselves ogling some shiny, new piece of gear thinking to ourselves, "Man, if I just had THAT, I'd have everything I needed." Of course, that's completely false and there's always that "just one more" piece of gear we'll find ourselves lusting after just months later.
But does that mean there's anything wrong with the gear we already have on hand? After all, it too was once that latest and greatest piece of gear. So is there really anything wrong with our old gear? Of course not. We just need to take a different approach to using it.
Consider, for example, how you can use some of the great freeware plug-ins out there to contemporize your instruments. Back in the 70's and 80's, musicians and producers were much more dependent on effects to make their synths sound more impressive. Take the time to see how you can use effects more - um - effectively to "modernize" the sound of your over-the-hill gear. Glitch it, gate it, sidechain it... Don't forget guitar stomp pedals or synthesizers with external inputs as other ways you can mangle your signal.
Don't stop there, though. Render a recording of your old gear to disk and get out the scissor tool, or a slicing program like ReCycle. Chop up your synth parts and retrigger those parts in creative ways. You can even go totally overboard and put each slice on its own track and process each one in drastically different ways. Even the lowliest gear can sound cutting edge and interesting through the use of some clever editing and processing.
Try sampling your old gear and seeing how you can manipulate the original sound with the facilities onboard your sampler of choice. Try extreme time-stretching, filtering, layering... and if you have something like Native Instruments Kontakt, Absynth, or Camel Audio's Alchemy, try out granular processing for some interesting ways to abuse sound.
Obsolescence only truly happens if we allow it to. Resisting that concept will encourage you to learn to push the gear you already have to do what you want, and your results will likely be a lot more unique if you do.