While perusing the Internet I came across references to UHAXNet PHPNuke Calendar v.1 Http://www.uhax.net Now the website was gone but I continued fishing until I found it. I haven't tried it yet, though I will. It appears it's for v6.9 and v7.0, but may work on other releases. If this looks like a nice module then I might take over development on it. Try it and let me know your findings.