While I await the new BattleTech game I've been indulging in MegaMek.
What is MegaMek you ask? Its a Java based digital form of the BattleTech board game.
Screenshot:
This campaign, MekWars, is super fun with fleshed out systems for economy, pilot leveling, planetary conquest, salvage, and repairs/reloading.
The best part of this server is its pick up and play. If you want to fight, message anyone and ask and you can begin a battle, simple as that.
The server wipes every six months or so and it just started a new cycle, so a great time to hop in!
If interested head over to http://npettinato88.wixsite.com/mekwars-dominion and download the client.
Read the rules, pick a formation, and log in. Once in, the mods will get you situated, its super easy.
Oh and this is Classic BattleTech with all the fixings, so expect combined arms (Mechs, Infantry, Aero, VTOLs, etc.)
See you on the battlefield, MechWarrior.