xCHM 1.19
"xCHM is a cross-platform GUI front-end to chmlib. xCHM can show the content tree if one is available, print pages, change font face and size, remember bookmarks, display a searchable index, and search for words in the current page and the whole book."
You will need wxGTK 2.6 or newer for xCHM 1.0 or later.