You must be an incredibly patient individual. I went online using my B&W G3 and page load times were agonizing. G4s seem to struggle, too. For a pleasant experience on the web, I think you need at least a G5.
G4s running optimized Leopard and a speedy browser like Leopard Webkit are still pretty useable I find.
G3s can be hit or miss. I actually find that they're not too bad most of the time in OS 9 with Classilla, although the rendering engine in Classilla is showing its age and really struggles with some sites(this one for example). I'm also using an Airport card(802.11b) on our unlocked home "guest" network.
In fact, yesterday evening I spent a while playing around with my 9600(2x200mhz 604E processors) running OS 9.2.2 and Classilla. That computer has a 10/100 card(onboard ethernet is 10baseT) that speeds things up a lot, and I have a "hot" graphics card in it-a Radeon 9200(temporarily, until I can finish my 8600 G4 project)-that helps things along a fair bit also. Most of the internet is okay, although it rolls over and dies when I try to access this site.
I can get this site to load in Classilla using a single 1.25 MDD, although it still doesn't render correctly.