Quick selection of random element in collection
Wouldn't advise this one in production code but if during testing you need to pull a random element from a pool of known good values you can quickly sort the pool by using
array.OrderBy(arrayElement => Guid.NewGuid());
To see it in action just try something along the lines of
var range = Enumerable.Range(0, 10);
for(int i = 0 ; i < 10; i++)
{
var newArray = range.OrderBy(arrayElement => Guid.NewGuid()).ToArray();
Console.WriteLine(string.Join(", ", newArray));
}