Yes, there have been virtual memory tweaks for the iPad1 when it was originally jailbroken, However, it simply is not as effective as you think it might be for a variety of reasons.
IOS had the facility built in by creating a com.apple.dynamic_pager.plist file in /System/Library/LaunchDaemons, where you could allocate as much storage as you liked to a swap partition. There were also a couple of dedicated JB tweaks for 3.x, and maybe 4.x, but I believe these are all long gone now.
The results betrayed the reason it was not pursued. SSD is "slow" (in terms of write) and virtual memory requires a lot of writing. The OS and Apps would demonstrate some lag as memory was swapped. This would be anywhere from less than a second, up to 30+ seconds which would compromise the user experience considerably. Battery also took a small hit (more important on the iPhone of course).
Overall, it just didn't provide the benefit that folks thought it would. Certainly not something that could be classified as "amazing". Lag is not a good tradeoff to keeping more apps in memory, and by the time you got past the lag, in many cases, a stock device would have re-loaded the app in to memory in any case...
Furthermore, the memory management in IOS has improved considerably over the generations and it is generally just better at managing apps and memory now. With 256MB RAM, iPad12 owners suffer the most of course.
Backgrounder is probably the best jailbreak solution if you are intent on keeping as many things as possible in RAM and running. You should certainly look into that, but you really need a "use case" for it. Just keeping everything running for the sake of it or because you 'can', as folks found out, isn't all it is cracked up to be
Also, I'm not sure how virtual memory can ever use ROM? The secret is in the name. It's read-only
