Now my operating system isn't so stressed anymore 
When Bitcoin was mining, often my system would lag, even freeze every few seconds. And this on a Core2Duo CPU. I now also have 400MB harddisk space free again now that the Bitcoin database is gone.
How can anybody take a currency serious that is dependent on electricity and where the maintenance costs more than what we get in return?
Just stop mining. If you can't mine efficiently, don't do it. You don't need to mine to use bitcoins. When Bitcoin was mining, often my system would lag, even freeze every few seconds. And this on a Core2Duo CPU. I now also have 400MB harddisk space free again now that the Bitcoin database is gone.How can anybody take a currency serious that is dependent on electricity and where the maintenance costs more than what we get in return?