To spawn objects, follow these commands to list all possible items to spawn, then to actually create the item:

1) Type: DEVELOPER 1 in console first. (this allows you to list the entities).
2) Type: ENTLIST, this will list the entities, and most things in the list are spawnable.
3) Use the GIMME cheat command to spawn the item.

Example: gimme item_weapon_microwavepulse will spawn the Microwave Pulse Gun.