I'd recommend mSATA SSD's in IDE adapters for any PowerPC-based portable.
I've had four of them, installed in:
- PowerBook G3 Pismo 500 MHz
- PowerBook G4 Titanium 867 MHz
- PowerBook G4 12" 1.33 GHz
- PowerBook G4 15" HR DLSD 1.67 GHz
They've served my needs quite well. They're noticeably faster than any spinning platter drive; just don't expect rocket-like performance - I think that's been oversold a bit. Your PowerBook has an ATA-100 drive bus that will limit the SSD's throughput, but it will make the most of it and you should notice a nice improvement over the stock HDD. Plus complete silence, cooler running, better shock protection and longer life.
Just make sure you choose well. Opening up a 12-inch "Little Al" is something best done only once if you can help it, those things are a real pain to work on. If there's anything else you'd like to change/fix, try to do it all in one go.
I've been very happy with the 120 GB
Intel SSDMCEAW120A4 in my 12-inch running Tiger. I have it in
one of these adapters [ATTN MODS: not my auction]. There are other options as well, that's just what I've used and am happy with. Do your research, open 'er up, and enjoy!