PLos One - leading open access journal in biological and medical sciences. A core objective is to "pursue a publishing strategy that optimizes the openness, quality, and integrity of the publication process."
PeerJ - offers a new open source publication model different from PLos One. "Authors must become PeerJ members to publish with the journal, but membership doesn’t guarantee publication; all articles must go through peer review and meet a basic standard of scientific quality. Emphasizing open access, PeerJ leaves the rights in authors’ hands and gives them control over when and how to share preprints of their articles."