As of the last 6 months, a small group of HL enthusiasts have been working on our new mod named "Half-Life: Static Friction". I am the coder so I have made a little trailer to show off what you can expect in our mod but I won't tell you the storyline, because that is not my department and it's not ready yet, but I can say it will be a major addition to the Half-Life storyline.
Trailer:
http://files.filefront.com/hl+sf+beta+previewwmv/;10117201;/fileinfo.html
Please give us some feedback and we are planning a Beta release in the near future.