(Always spelled with a single M) Taking pictures of cats and posting them over and over on a forum, email, or instant messanger. This is done by finding various links of cat pictures, and spamming your friends or enemies over and over agin until they start yelling at you, or log off. If used properly, cat spaming should annoy the crap out of whoever you cat spam.

The safeguarding of Earth and other worlds from biological cross-contamination (i.e. billionaires with too much time on their hands).

Also known as “planetary protection.” Planetary protection / quarantine “reflects both the unknown nature of the space environment and the desire of the scientific community to preserve the pristine nature of celestial bodies until they can be studied in detail.”

There are two types of interplanetary contamination. Forward contamination is the transfer of viable organisms from Earth to another celestial body. Back contamination is the transfer of extraterrestrial organisms, if such exist, back to the Earth's biosphere.