Amy Editor uses very clever technique for storing changes to document. It allows such features as unlimited undo/redo, as well as collaboration running in transaction over the internet. One usefull side-effect is the "last changes" sidebar. It is located in the right sidebar and shows last changes to the document. It visually reflect position in document as well as time of the change - all changes fade away in time causing most recent ones to be more bright. If you collaborate on a document with someone else, the sidebar changes splits so you can visually see the changes the other person made. Not only you can see the changes, you can actually click on the colored bar and Amy will change your scrolling and caret position so you can see it without search. This feature is a subject to change in next releases.