@microid
Welcome to A.org :-D
Are you talking about the writing on the inside case of the A1000? If so, you certainly don't want to erase it (ie sand it down) - those are the signatures of the original Amiga team (and Jay Miner's Dog's pawprints :-) )
Or do you mean some application where you can scan in a picture and remove writing off it? :-?
---edit---
If you've bought a second hand Amiga that someone's written all over, taking the case apart and immersing it in some kind of cleaner (I cannot remember what's best) should get the writing off I'd imagine, and maybe even help get rid of the yellow colour.
