Firefox, pero recently may na discover ako bug ng Firefox 2, yung bookmarks kapag di mo na shutdown yung PC mo properly (pero di naman palagi - 3 times na nangyari sakin) mawawala lahat ng bookmarks or let's say ma rereset yung firefox 2 into fresh install state, mawawala yung saved cookies, yung history and most specially the bookmarks,. lets say out of 10 times na di ko properly na shutdown yung PC ko w/ Firefox on, 3 times nag roll back to fresh install yung firefox ko even even though naka disable yung system restore ng windows ko.... sana maayos nila toh... i only use IE and OPERA to test yung mga trabaho ko if properly compliant to all type of users.