I tried eXtplorer a few months ago with Joomla! 1.0.13 and even though I liked it immediately and could see its potential it kept logging me out so was not usable at the time. But after the upgrade to J! 1.0.14 and an upgrade in eXtplorer itself I tried it again and it just blew me away!!!
The installation went smoothly without any problems. Once installed you are ready to go, no configuration needed.
Apart from seamless file manipulation (moving, copying, CHMOD etc) it has a wonderful zip file utility which makes transferring a large number of files a breeze and one of the coolest features is the file editor which has code highlighting and an "apply" feature which in combination with the AJAX makes editing files on the server so enjoyable! Just edit your file, apply the changes (without reloading the page) and just go see the effect immediately on the site front-end.
The verdict: A must have for "EVERY" Joomla! site, in fact, it's so good it should be included with core Joomla!
My thumbs up to the developer(s) and a big THANK YOU for making such a great tool free. God bless you.