The big deal about rambus is that a few years ago, intel made a deal with rambus so intel's chips and motherboards would only use rambus memory, essentially producing a monopoly on memory. Rambus had duped the international standards committees into using technologies it had secretly patented, so at the same time Intel tried to force the whole world to switch rambus, rambus tried to force all other memory manufacturers to halt production on SDRAM and almost all competing memory types through patent lawsuits.
It all horribly backfired when a few things happened. First, rambus got their butts handed to them in court when it was discovered they'd lied like potatos when they participated in the standards committees and led the SDRAM standard into using previously patented ideas. Second, it turned out that rambus memory had higher access latencies than SDRAM so even though certain benchmarks would show rambus as being faster, SDRAM was just as fast in most real world applications. On top of that, the other memory manufacturers went into overdrive and in under a year doubled the bandwidth of regular SDRAM, further decreased it's access latencies, and also came up with DDR SDRAM, all while rambus was being countersued out of existence. Rambus promised reduced access times eventually but alternative chipsets that could use SDRAM sprung up all over the place and the company went broke.
Intel finally gave up on their end of the bargain after being humiliated both in public and in the courtroom even though they'd been including 128 meg of RAMBUS free with many intel motherboards, and so they released their next chipset with SDRAM support. Some industry insiders think that Intel had anticipated this possible outcome, had secretly created the alternative chipset, and simply held onto their SDRAM chipset until it was polite to release it.
But for a while, new high-end intel motherboards required expensive and proprietary RAMBUS RDRAM memory. That technology is still good enough in server applications that many aging servers and what used to be high-end desktops or workstations have not been replaced and still require rambus upgrades on occasion. It's a dead technology however, so it's pretty expensive stuff to find. At the time, a rambus system was the fastest you could find but the marketplace and the realities of our legal system ensured that the attempt to become a monopoly ended up being the very factor that killed it in the end.
