Cargobob
The Cargo Bob is a helicopter found on Grand Theft Auto: San Andreas. It is the largest and heaviest helicopter on the game and the hardest to obtain (by sitting in the middle of the restricted area in the desert guarded by SAMs).
For those reasons, it is the most underused helicopter on the game, as the other helicopters are relatively easy to find after all the cities are unlocked.
However what many people do not know the Cargo Bob is a truly special vehcile. The interesting thing about it, is that it has a large cargo door at the back of it that can open by pressing down the analog stick on the PS2. One or more motorcyles (if not a car!) can fit in the back, making this helicopter the ultimate vehicle for moving bikes (possibly cars) from one garage to another. Unfortunately for all these benefits there is a price to be paid so the Cargo Bob has no form of defense, and also due to its very heavy weight it is hard to do turns, adjust altitude, evasive manouvers, etc.
The easiest way to get it (only for those of you who cheat) is to use the "Wanted Level Never Increases" and "Deadly Vehicle" cheats. That way A: you can steal the Cargobob without the 5-Star Wanted Level, and the SAM Missiles (Area 69's SAM Missiles shoot at you even with the "Wanted Level Never Increases" cheat on) won't destroy you. Then park it in your garage at Verdant Meadows. For those of you who don't cheat, I suggest that you get into Area 69 through the nearest entrance to the Cargobob, since the Police won't get there right away, and fly like fuck. As for the Wanted Level afterwards, three words: Pay N' Spray.