This page contains various attempts to prevent linebreak between images. NBSP should work but doesn't; and even if it did work you get an unwanted visible gap. ZWNBSP should work but doesn't; and even if it did work many browsers would display an unwanted black box. CSS2 does let you control pagebreak, but it appears to miss linebreak.
To see the problem, gradually narrow the window size, and you will see that only #2 works, but it is an awful hack, and the vertical alignment gets dicey. [This is all with IE 5.5.] Anyone have a suggestion for a better better approach?