Here are some funny videos from 3 different guys on Youtube.
First is Jack Vale. He is most known for his "farting" videos where he goes around in public with a device that makes a farting noise and records peoples reactions. Lately he has been branching out into other videos such as this one called Hearing Things, where he goes up behind people and quietly says "sir" or "mam" but then pretends he didn't say anything. The results are very funny. Check it out.
Jack Vale - Hearing Things
Next is Uncle John who is related to Jack and makes similar hidden camera style videos. In this one, they both play tricks on grocery shoppers by putting things in their basket when they are not looking.
Uncle John - Fun With An Orange Ball
Lastly is Ed Bassmaster who is a great prankster and has a lot of different characters and voices he does. Here is one where he does the farting video in Time Square. Make sure to watch the 2nd half of the video as it becomes crowded and people start to catch on and it literally becomes a show.
Ed Bassmaster - Ultimate Farting
If you liked these videos, be sure to check out each of their channels for a lot more hilarious videos.