Free Flash-based image viewer. Allows embedding a larger image in a box within a web page, and allows users to zoom and pan within that image.
Go to the Sourceforge site
In the web page, just upload the SWF file to the server and use this code:
<object classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" codebase="http://fpdownload.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=7,0,0,0" width="600" height="500" id="ImageViewer" align="middle">
<param name="allowScriptAccess" value="sameDomain" />
<param name="movie" value="SWF-FILE?imageUrl=IMAGE-URL&w=WIDTH&h=HEIGHT" />
<param name="quality" value="high" />
<param name="bgcolor" value="#ffffff" />
<embed src="SWF-FILE?imageUrl=IMAGE-URL&w=WIDTH&h=HEIGHT" quality="high" bgcolor="#ffffff" width="600" height="500" name="ImageViewer" align="middle" allowScriptAccess="sameDomain" type="application/x-shockwave-flash"
pluginspage="http://www.macromedia.com/go/getflashplayer" />
</object>
...and fill in SWF-FILE, IMAGE-URL, WIDTH (in pixels) and HEIGHT (in pixels).