Gift for my parents, at graduation Options

[kcroxyoursox]

So graduation is a week from today and afterwards (we are in the morning ceremony) we are going to lunch at Stella's. I want to do something for my parents as a thank you for all of the things they have done/sacrificed to get me where I am today. I want it to be nice, but I don't want it to cost a lot because I don't want them to be upset I'm spending lots of money on them instead of saving for rent and such.

I wanted to do a photo collage of sorts that had pictures from all my college years and then leave one spot blank for a picture of me in my cap and gown. However, frames with enough slots for what I want to do are way too expensive.

Anyone have any similar ideas? I want to do something that says thanks that's thoughtful but won't break the bank.

Also, would it be inappropriate to give these gifts if we didn't have something to give to the others (aunts/uncles/grandparents/close friends)? They too are traveling out just to see me walk across a stage...

I am pretty set on wanting to do something for my parents if nothing else.