Almost every day I tweet an interesting links to the freeware HD wallpapers collections like this:
http://wallpaperwhd.blogspot.com is a website where you can get cool wallpapers. It is very good quality and it’s free. If you are looking for high definition wallpapers for your Windows desktop just follow me on Twitter: http://twitter.com/perevoznyk and you will receive the regular update about HD wallpapers available for download.
Download Erupting Volcano wallpaper, ‘lighting and volcano’.
From National Geographic wallpapers section: