On Tuesday, 49ers wide receiver Michael Crabtree was cleared to practice for the first time this season. He has been on the Physically Unable to Perform list after tearing his Achilles tendon in May. He is still on that list, but now that he is eligible to practice, the team has a three-week window during which they can add Crabtree to the active roster at any point. So, he will be eligible to play in Week 13 at the latest. However, according to Mike Maiocco of CSN Bay Area, Crabtree's 2013 debut could come before that Dec. 1 game if he looks sharp in practices.
The 49ers will probably take their time with Crabtree. I wouldn't expect him to play prior to Week 13 and even then, his snaps will probably be very limited for a couple of weeks as he ramps up his activity and works his way back into football shape. Take a shot on Crabtree if you would like, but I don't think he'll give much of a boost to any fantasy owners this season.