Worth signing Biggio? He's not been good at the plate for a few years now, but he was just DFA'd and should be available. Even though his bat hasn't been good, he is still - in limited games and at-bats - producing + bWAR. Like, even this year, as he's hitting .200/.323/.291/.614, 80 ops+, he's still given Toronto 0.4 bWAR in 44 games. Which obviously isn't great, but +0.4 bWAR is more than the following guys have given Boston this year:
Yoshida (0.2)
Casas (0.2) - not saying he's better than Casas, obviously
Story (0.2)
Dalbec (-0.3)
Smith (-0.4)
Valdez (-0.5)
Grissom (-0.6)
Reyes (-0.8)
Cooper (-0.9)
So he'd actually represent an upgrade over a bunch of guys on the team who have played a considerable amount.