The stated requirement for OS X PB is 128mb of RAM. To really make it perform best, however, more seems to be much better. This is especially true if you run a number of large Classic apps, such as GoLive, Excel, Word, Photoshop, etc.
The amount of disk swapping that goes on drops dramatically with increased RAM, making the system much more responsive overall. There was even a notable difference between my home (192mb) and work (320mb) machines, which are otherwise identical G4's, so I decided to upgrade the home machine.
I ended up adding 256mb (for about $150), and the differences are dramatic. I hardly ever hear my hard drive now, unless I'm accessing it. Read the rest if you want the details on where I bought my RAM...
Doing a little search on the web revealed that RAM is reasonably cheap right now. For example, G4 RAM prices at Other World Computing were as follows on 12/12:
32mb: $27.99 || 64mb: $37.45 || 128mb: $63.75 || 256mb: $116.99
These are their "generic" RAM prices, but even the brand name stuff isn't bad. Oh yea, they're also having a shipping sale - overnight FedEx for $4.95. I ordered the non-generic 256mb module. Total bill including overnight was about $150. Installation took two minutes, and my G4 now feels very snappy in the PB!
I have no connection with Other World, and you can probably find similar or cheaper prices elsewhere. The point is just BUY SOME if you can ... or ask for it as a holiday present! :-).
Mac OS X Hints