This page documents my experience with the Nokia 6600 slide
Enter the following cheat code: *#0000#
Other cheat codes can be found on the relevant wikihow page
You want to send contact information to e.g your PC or another phone via bluetooth: read on.
Internally, the phone uses the vCard format, so each contact will be sent as a vCard file.
Go into the contact menu. Select the name contact you want to send, click on it, then go to Options -> Send business card -> Via Bluetooth. The Send business card item is hidden down the long list of options.
If, say, you want to send all your contact information to your PC, then you are out of luck: I haven't found how to do it in an automated way.
That means you will have to send each contact using the single vcard method.
The lack of such an important feature is one of the reasons I wouldn't recommend buying this phone.
To raise the volume during a phone call, move up the stick. To lower it move the stick down.
The lack of volume buttons on the side makes the above procedure annoying, and is another reason why this phone sucks.