I have switched to Chrome because it supports my tabaholism better than Firefox, but then even it started to get bogged down by it. I am using Instapaper to save things to “read later” even though I know I will forget to ever look at them again. Then I discovered this extension for Chrome called “toomanytabs”, which lets you suspend tabs for later, and tells you how many you have open other than those suspended. Great! I thought this would solve the problem. But this just seems to enable my tabaholism even further. I have 35 tabs open in Chrome even after suspending dozens of them. ARGH. At least the fact that it shows how many are active kind of shames me into trying to close some 
@Wrong_Writer – Thanks for the suggestion! I will definitely try out the tab suspender extension you recommended for Firefox! I was using the tree-style tabs extension in Firefox, which shows your tabs down the side of your browser instead of along the top, and lets you nest them. It is wonderful for tabaholics. There are about a zillion open in that but I just “saved all tabs” & closed it for now because Chrome is slowing everything down enough.