Apple's 1998 Powerbook G3 Series (codenamed "Wallstreet") commonly suffer from worn out LCD hinges. The main symptom of this problem is an LCD screen that just won't seem to stay in the upright position. The most likely cause of this is a broken or worn out hinge, or clutch assembly inside the machine.
I recently encountered this problem with a computer at work. Fortunately, I had an extra inoperable Wallstreet PowerBook with properly functioning hinges and decided to swap the parts out. I was a little wary of doing this at first, but it ended up being a very simple fix. I took pictures and have posted them in hopes that they will help someone fix their broken hinges.
So, to begin the "tour" click the arrow below. If you have questions of comments about this procedure, email me.
UPDATE: Thanks to some very helpful readers, I have found a place to purchase these hinges. So, if you're ready to replace your own hinges, head on over to pbparts.com and pick up a replacement set of hinges!