Pretty cool app - ShakeIt:
Androlib link here
- allows you to shake the phone to unlock the screen
- allows you to flip the phone upside down to enable speakerphone while on a call
If you're trying to get the speakerphone to turn on, you need to point the screen towards the floor to get it to turn on. I haven't tested in a call besides my voicemail, but I noticed that when I point the screen in other directions, the speakerphone turns off but the phone says it's still on. Therefore, I am unable to manually turn on and off the speakerphone in a call - I would be stuck pointing the screen to the floor to have the speakerphone active.