If you are an happy macbook or macbook pro user, read on - this may save your hard drive!

Remember your old iBook or Powerbook? You closed the lid, tossed the laptop into your bag and off you went to somewhere else. Do you still have this habit with your shiny new Apple hardware? WRONG! You can't do that! It will seriously bork up your hard drive, as for example discussed in this thread.

Here's the reason: On newer hardware, Apple enabled that fancy SafeSleep option per default. It will not immediately put your mac to sleep, but will first make a back up of your ram onto the hard drive, to protect your session in case your battery runs flat during sleep. It's a good thing to have, however the write process may take up to several minutes if you have a lot of ram (i have four gigs and it takes quite a while). Apple's manual mentions this:

"NOTICE: Wait a few seconds until the sleep indicator light starts pulsing (indicating that the computer is in sleep and the hard disk has stopped spinning) before moving your MacBook Pro. Moving your computer while the disk is spinning can damage the hard disk, causing loss of data or the inability to start up from the hard disk."

Good that nobody of us reads manuals. And really, who will stare at their lights to figure out if it's flashing, one is having hallucinations, or if it's lighted up continuously?

All experts agree, moving your Laptop during excessive write progress is not an good idea, and tossing your laptop into your bag during that time will seriously cause you several days of ache.

Luckily there's an easy way to fix this, without having to give up SafeSleep: SmartSleep

"SmartSleep let's you select each select sleep state. Additionaly the new SmartSleep state lets your notebook just sleep while the battery has a high level. If the battery level drops below a certain point ( default is less then 20% or 20 minutes ) it will switch to sleep and hibernate. So you have the best of both worlds."

That means you can close the lid, toss your laptop into the bag, and go home again, just like in the good old times. Should you forget your laptop somewhere over the weekend, your logged-in session is still save.