I want to point out that I didn't write any of these, but here you go. Wanna post your own? They've gotta rhyme and be of the 'What am I?' sort, which by the way, all of these are. Have fun.

I.

I am what you want
And what you fear
A hidden movie
Behind your ear

*Not a secret

II.

Letter by letter
You may find yourself ranting
A stream of spoken words
That some find enchanting

*Not a song

III.

A party of tears
And a liquid trail
I try to sleep
But to no avail

*Not a river

IV.

On the wall I may be found
Or from heaven I'll come down
To teach
To warn,
Or to astound
I'll help the lost
If I am found

*Not a star