I saw this over on the Brewers blog and decided it was a cool thing to post because I usually forget most of these dates. Enjoy.

2008-2009 MLB Offseason Dates Worth Knowing

• Starting with the day after the conclusion of the regular season, players can be traded with no waiver rules in effect. It was originally September 29 this year, but with the extra games I suspect they pushed it back to October 1. I don't think it impacted anyone anyway. Trade announcements are probably encouraged to be postponed until after the World Series.
• October 15 was the first date when players with 3+ years of service time who were outrighted to the minors at any point during the season, accepted the assignment, and still haven't returned to a major league roster could declare free agency. Players who were outrighted for at least the second time in their career, accepted the assignment, and weren't placed on a major league roster again could do the same.
• The 1st day after the World Series is the first of a 15-day period during which eligible players (6+ years of service time, no contract for next year) can declare free agency.
• The 16th day after the World Series is the first day Major League free agents can negotiate and sign with a team other than their former team. It's also the first day MLB teams can sign minor league free agents.
• The General Managers meetings are held in Dana Point, California, from November 3-6.
• November 20 is the day teams have to file their reserve lists for all major league and minor league levels. I think that's the day you say who you want to protect in the Rule 5 draft, but I could be wrong.
• December 1 is the last day for teams with Type A or Type B free agents to offer arbitration to them, provided they haven't signed with another team yet. The player would have to accept within a week. If a Type A or B free agent signs with a team other than his former team before December 1, his former team gets draft picks regardless of whether or not they had offered arbitration to the player.
  
• December 4 is the last day to request outright waivers to assign guys prior to the Rule 5 draft and December 8 is the last day to outright players prior to the Rule 5 draft. The Rule 5 draft takes place on December 11.
• Not coincidentally, the Winter Meetings in Las Vegas take place from December 8-11.
• December 12 is the last day to tender contracts for 2009 to guys you want to keep around. 
• Between January 2-12, teams must notify players eligible for arbitration that they wish to offer them arbitration. Players can agree to go to arbitration at any time between January 5-15.
• By January 18, the team offers and player offers for arbitration are shared between the MLBPA and the MLB Labor Relations Department.
  
• Arbitration hearings are held between February 1-20.
• Injured players, pitchers, and catchers may be invited to spring training no earlier than February 20 (45 days before the start of the regular season). All other players may be invited to attend no earlier than February 25 (40 days before the start of the regular season). No player is required to report to spring training more than 33 days before the start of the regular season, or March 4 next year, though inevitable "visa problems" can delay that for some guys.
  
• If a team and player tendered a contract haven't agreed on a salary for 2009, contracts can be renewed between March 2 and March 11. The maximum salary reduction rules mentioned above still apply.
• In order to only owe a player 30 days of termination pay, he must be unconditionally released on or before the 16th day prior to the start of regular season. For next year, that's March 22. Any player released after that date but during spring training gets 45 days termination pay.