If you happen to be in the beautiful city of Berlin for LinuxTag in a few days, don't miss "OpenSource-Fonts – Bedeutung und Nutzen von freien Schrifttypen in Theorie und Praxis" by the authors of LinuxLibertine. (If you don't understand deu aka German: it's "Open fonts – meaning and usage of libre fonts in theory and practise").
Linux Libertine and Linux Biolinum are truly amazing open font projects with plenty of smart font features (including TeX integration). No doubt this represents a huge amount of work. Well-worth checking out and contributing to.