how do you know when you've blown a speaker?

I have a tendency to "crank it", and was wondering how to tell if i have a blown speaker. Is there any quick way to tell?
You can usually spot a blown driver/tweeter when something sounds funny with the bass. One way to check them is to FIRST - TURN YOUR SYSTEM DOWN!, then go around to each driver/tweeter, put your ear up close and listen for any imperfections (usually a snap crackle or pop or no sound at all).I sometimes use a couple pieces of cardboard to deflect the sound away from the driver I am checking, or cup it with my hands.

I usually use something a little bassy as source material. This seams to work pretty good as I have pin pointed two blown tweeters over the years with this method.
When you wake up with a terrible headache,and glance over to your left to see a Thiel 3.6 laying next to you, smoking a Camel. That's a sure sign!
You're a sick puppy Jmslaw - I love it! Now go and gargle to get that nasty taste out of your mouth!

Oh, the jokes that could be made about "blowing a woofer."

i'll leave that to marco . . . .