Hi,
Using a Ram disk is ok for some applications, but for people that dont know how they work, by storing data in ram not the hard drive, it could cause some minor problems. The problem would be caused when or if they shut down their computer or turned it off they would loose all data on the ram disk, most ram disk applications do not automaticly save to hard drive at system shut down. A person would have to remeber to back up the data to the hardrive every once in a while to prevent data loss.
Otherwise a Ram Disk would greatly improve on the speed of the responses for Hal database's since they are stored in ram it would take little time for data access. One small problem is that you need to have enough spare ram to create one as well. It would not work well on systems with less then 512 MB of ram, prefered 1024 MB Ram.
Just a little information for those who dont know what they are, I hope this helps in some way.