Place for C# util libs?

Is there a place i could get C# util libs? I dont mean big libs or things like zlib. Something like a collection of helper functions like getting the most leftmost subdomain, fixing the /'s and \'s in a filename (i know its easy but still), writin开发者_如何转开发g the BOM for a textfile (maybe this exist but i dont know it), etc.

Just for the "collection of helper functions", you might want to check this thread: What are your favorite extension methods for C#?

It's basically a collection of small utilities, that have also been collected in the ExtensionOverflow CodePlex project.

There are several interesting things there. I don't know about the things you are asking explicitly, but it's surely worth a look...