I understand what you mean, but in my case I just need to run Firefox and Thunderbird, and little else…
Check this Porteus 5.0rc2 running XFCE with Firefox with 3 tabs open, all entirely from RAM, in a Vbox with just 4GB of RAM… it’s using just about 700MB of RAM (and every config file changes will be saved to HDD on poweroff or reboot)
