What does the icon (a red plus sign) in Subclipse mean? What do I do if I want to get whatever is from the repository regarding this file?
This is a merge conflict icon, more specifically a tree conflict, where a file has been created twice. This blog post also explains how to resolve them.
A tree conflict occurs when a developer moved/renamed/deleted a file or folder, which another developer either also has moved/renamed/deleted or just modified.