Printers and Cartridges

We have been fed with the story that using anything other than authorized cartridges would ruin our printer. It is, of course, entirely plausible that it will indeed ruin our printers. But on the other hand, cartridge technology (or ink technology for that matter) isnt rocket science.

There are companies that can refill our print cartrides for much cheaper than the original manufacturer would do so. To me this seems logical given that technology is not so scarce. (Well, any spurious product will harm you, but I am assuming that companies that refill are not into spurious products.)

And if printer companies priced cartridges so that they could milk their printers for a long time, then these guys are the right spoilsports...

I recall cameras of X brand saying, for best results, use X brand film and we all knew that it was a lie. So how different is it with printers?