Motivational? Inspirational?

I've been trying to come up with a song to use as a theme for this journey I am taking.  All my life, songs have marked milestones along my way and it just seems that there should be one for this too. 

Now, I suck at being able to think of songs I like, but if someone says the name of a song, or I hear a song on the radio or on television, then it hits me how much I like that song.  Then it is in to the computer to find it to download to my ipod.

So, I need ya'll help.  Give me your songs.  Those at motivate and inspire you.  Give me some suggestions.  The forum is yours.