title: Implementing your own LINQ & IEnumerable<T>
body: <p>In a project I am working on, there are really huge collections (1M-1B elements), and things are modified as collections mostly.</p>
  
  <p>It's a real-time app, and so the performance is paramount.</p>
  
  <p>For some of the operations, like Reverse, BinarySearch (possible?), etc will suffer more than others like Select, etc.</p>
  
  <p>Is it feasible to implement one's own IEnumerable with possible MoveNext, MovePrev, etc and own implemented LINQ extensions that take advantages of these?</p>
  
  <p>If this is gonna happen, it's gonna happen at the end of the project. Because we need to get it working first, then make it faster.</p>
  
  <p>All in all this shouldn't be too much work, right?</p>