Good morning Goldy! I personally do not think they are worth too much as the .com, let alone the .biz. I would say they are worth $regfee the most, good luck!
If you have .NET as the extension, then it may worth a while to get them depending on the actual combination. C-D.net would not be too bad, but do not expect to yield a high amount from them.
I regged C-M.net a while back, I dont think the reg fee will be lost, I was going to partner with someone from the US on a few projects, his name was Chris and mine obviously Mike, it can also be used as in Chantale & Mike, Chantale is my Wifes name
I made a logo for it if you wish to view its on my home page at www.TLDN.com