Mohammad Ali Abtahi was once Iran's Vice President and is aligned with the country's reformer President Mohammad Khatami. Abtahi didn't want to disappear into oblivion so he started a blog to communicate with his supporters.
Read 1 Pissed Arab, an Egyptian "provoked by both Arab and Western media coverage and felt that the Arab moderate view is terribly lacking in representation."
Paris-based Reporters Without Borders are currently running an online poll to find the best blogs defending the freedom of expression. "These awards will be in tribute to webloggers who defend free expression and sometimes pay heavily for it. Two of them are, for example, still in prison in Iran."
UPDATE: This list gives a range of bloggers across the world fighting oppression in their homelands.