>>798
ReadKey回すしかないんじゃない？こんな感じで。

StringBuilder sb = new StringBuilder();
ConsoleKeyInfo cki;
Console.Write("Password: ");
do
{
while (!Console.KeyAvailable)
{
Thread.Sleep(10);
}
cki = Console.ReadKey(true);
if (cki.KeyChar != '\r' && cki.KeyChar != 0)
{
sb.Append(cki.KeyChar);
Console.Write("*");
}
} while (cki.KeyChar != '\r');
Console.WriteLine("\nYour Password is: " + sb.ToString());