To, Too, Two...so hard to remember which one to use!

Too many people confuse to, too, and two.  Every once in awhile doesn't bother me since it could be a typo.  However, when it happens daily on a status update, you  know the person just can't tell the difference.  (This coming from the Queen of run-on sentences and excessive use of ellipses...)

Here's a reminder to all of those who have forgotten the meanings...

To

To has two functions. First, as a preposition, in which case it always precedes a noun.

I'm going to the store

Secondly, to indicates an infinitive when it precedes a verb.

I need to study

Too

Too also has two uses. First, as a synonym for "also":

Can I go too?

Secondly, too means excessively when it precedes an adjective or adverb.

I'm too tired

Two

Two is a number.

One, two, three...

Neurotic much?  :)