I just signed up at a hosting company to launch a new series of web sites and my primary consideration was their support for FOSS.
My number one issue was whether they had Cpanel available for my use, but specifically Cpanel with Fantastico. According to the developers site, Fantastico "is the leading autoinstaller for cPanel servers. With more than 10.000 installations, it provides more than one million end users the ability to quickly install dozens of the leading open source content management systems into their web space."
I find that Fantastico, with its pleathora of FOSS, makes setting up a variety of web presences extremely easy; in fact (and I must admit my newbie status in all this), most of my exploration of free and open source programs has been through those made available by Fantastico. The ease of use with Cpanel's integration of Fantastico makes it a slam dunk for any newbie to really begin to make some great web sites with ecommerce, photo gallery, auction, social networking, crm, and blogging capabilities.
There are of course a few open source programs I use that aren't in Fantastico, but come with Ubuntu like Gimp, Open Office, Skype, GAIM, etc. However, these are mostly desktop programs and not web programs. I also use SugarCRM which is a great CRM which I also installed independently.
I've added my favorite programs from Fantastico below.
Joomla! (visit site)- a Content Management System (CMS) created by the same team that brought the Mambo CMS to its current state of stardom
Geeklog (visit site)
ZenCart (visit site) - another user-friendly open source shopping cart system
b2evolution (visit site)
Nucleus (visit site)
pMachine Free (visit site) - great tool for managing your own personal blogging site or mini portal
WordPress (visit site)
4images Gallery (visit site)- your own online photo gallery
Gallery (visit site)- probably the most popular image gallery script
Coppermine Photo Gallery (visit site)- a feature-rich photo gallery script with MySQL database, usermanagement, private galleries, automatic thumbnail creation, film strip, and a template system for customization
Moodle (visit site)- Moodle is a course management system designed to help educators create quality online courses
Noah's Classifieds (visit site)- run your own Classified ads website!
Open-Realty (visit site)- professional but free tool for real estate agents to put their offers online
Fantastico has a lot more; all I can say is that it's well...I won't actually say that...!