FREEZER BAGS: They are male, because they hold everything in, but you can see right through them.
PHOTOCOPIERS: These are female, because once turned off; it takes a while too warm them up again. They are an effective reproductive device if the right buttons are pushed, but can also wreak havoc if you push the wrong Buttons.
TIRES: Tires are male, because they go bald easily and are often over inflated.
HOT AIR BALLOONS: Also a male object, because to get them to go anywhere, you have to light a fire under their butt.
HAMMERS: Male, because in the last 5000 years they've hardly changed at all, and are occasionally handy to have around.