I ask though I doubt there is any such system.

Basically I need to schedule tasks to execute at some point in the future (usually no more than a few seconds or possibly minutes from now), and have some way of cancelling that request unless too late.

Ie. code that would look like this:

var x = Scheduler.Schedule(() => SomethingSomething(), TimeSpan.FromSeconds(5));
...
x.Dispose(); // cancels the request

Is there any such system in .NET? Is there anything in TPL that can help me?

I need to run such future-actions from various instances in a system here, and would rather avoid each such class instance to have its own thread and deal with this.

Also note that I don't want this (or similar, for instance through Tasks):

new Thread(new ThreadStart(() =>
{
    Thread.Sleep(5000);
    SomethingSomething();
})).Start();

There will potentially be a few such tasks to execute, they don't need to be executed in any particular order, except for close to their deadline, and it isn't vital that they have anything like a realtime performance concept. I just want to avoid spinning up a separate thread for each such action.