I use a Dell 24" external monitor with my 2009 13" MBP. 75% of the time, my MBP lid is closed, and I'm hooked to power and monitor and ethernet cable. I also use a BT Apple KB and mouse in this configuration. Sometimes, though, I'll go work from the couch or something, and everything's unhooked. Here's my issue: I might drain my battery down to 35% remaining while working on the couch. I don't want to recharge the battery until I drain it completely. Battery management debates aside (i.e. this isn't likely needed anymore, etc.), here's my problem -- when I return to my desk, I want my MBP to run plugged into ethernet and the monitor, with my BT devices, but NOT plugged into power. But I can't get my laptop to wake up and power the external monitor. I've tried hitting the return key on the BT keyboard. The external monitor wakes up for a second, I see the screen, then the MBP goes back to sleep. I've tried opening the lid and closing it again really quickly. The MBP just goes to sleep. I've tried opening the lid, allowing it to mirror the screen to the Dell24", then close the lid again. It can run fine on battery power, mirroring the screen, but as soon as I close the lid, the MBP goes to sleep. It's like it only has three settings -- plugged into power and powering the external monitor, unplugged and powering the 13" laptop screen, or unplugged and powering the laptop screen mirrored to the Dell. How can I get it to run, with lid closed, powering only the larger Dell monitor (I don't want it running the laptop screen because then it drops the resolution of the Dell well below specs, and I don't want a dual screen, because I find that two confusing). Thanks.