How many timers are in the .NET Framework? What assumptions do they have? Which timer would you use for implementing Speculative query execution?

How many timers are in the .NET Framework? What assumptions do they have? Which timer would you use for implementing Speculative query execution?
Warning: this post won’t be about “boring” or “typical” algorithms from Computer Science which we all have learned on studies (like quick sort, merge sort, xxx sort, A*, FFT). Instead, this will be about other little-known, especially USEFUL algorithms, which people working as professional developers should know or heard of.