I probably nabbed that DDR1 RAM you were looking for. It fits nicely in this old P4 I have.
For you, you ought to just save the money and buy an Intel 40GB X25-V SSD, which is about $125 USD now. I have the iRAM, and the spiritual successor to it, the ACARD ANS-9010 (B). The iRAM's battery started to bloat, so I had to remove it, and later replaced it with the ACARD because of memory capacity issues.
What do I think about them? They're not worth the money these days, especially if you can get an SSD. I got the two RAM drives when SSDs weren't available. The situation has changed now, and you are MUCH better off with an Intel budget SSD (the X25-V, the same as the mainstream 80GB X25-M one, just 40GB) because it has higher capacity, generally better performance, is non-volatile, and is cheaper overall (especially vs. the ACARD).
If you have a bunch of DDR1 or DDR2 RAM laying around, and can find an iRAM or ACARD for cheap, by all means get the RAM drives. However, if you are just thinking of getting one, save the money and get an SSD, or more physical RAM for your motherboard.
Performance-wise, the SSD is usually better than the RAM disk. I've attached some CrystalDiskMark results to this reply. The C: is the Intel SSD, the M: is the ACARD. For random IO (the most important), the ACARD only excels with the 4K random read/write. Sure, that's very important, but the SSD is far better in the other benchmarks, and especially in the 4K QD32, which performs random read/writes in 32 separate threads--the more likely random IO scenario taking advantage of native command queuing, etc. If you're thinking of putting your swap file on the RAMdisk for a bigger disk cache (my initial use), you're better off just reading the data straight off the SSD than caching it (not saying you won't need virtual memory in general however).
All in all, save your money for an SSD.