How could I improve this C# randomising method?

Question

I think I\'ve settled on this as the most simple and unit-testable method for randomising a list, but would be interested to hear of any improvements.

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Answer 1

I liked Dennis Palmers idea of returning a shuffled IEnumerable instead of shuffle the list in place, but using the RemoveAt method makes it slow. Here is an alternative without the RemoveAt method:

public static IEnumerable Shuffle(IEnumerable list, int seed) {
  Random rnd = new Random(seed);
  List items = new List(list);
  for (int i = 0; i < items.Count; i++) {
    int pos = rnd.Next(i, items.Count);
    yield return items[pos];
    items[pos] = items[i];
  }
}

I thried this with 10000 integers, and it's about 30 times faster.