This is a sweet giveaway! I keep telling Linus that I need some free products to help build a computer for my fiancee. She is still using a computer from 2008 with a 2.3GHz dual core processor and a 9800GT graphics card and she is always trying to steal my computer from me. I built it based upon a lot of the products featured on LinusTechTips.
Anyway, my favorite video from LinusTechTips was his video on the Sennheiser HD 8 DJ headphones. I had heard Beats by Dre before and I actually laughed at how bad they sounded. I thought high end headphones were a total waste of money. But after watching Linus talk about the amazing sound quality available from high end headphones made by high end audio equipment manufacturers I began a search for a quality set of headphones. Because I don't yet have a DAC/AMP, I decided to get something that would be easier to drive, reasonably priced, and still high quality. So, after a lot of research I went with the Audio Technica ATH-M50x. I also plan on getting a pair of Sennheiser HD-600's and an Objective 2 with ODAC after seeing those products on the LinusTechTips channel and reading many positive reviews. My fiancee loves my new ATH-M50x's, so I doubt she'll complain too much when I upgrade.
My favorite video from JayzTwoCents is his video on the budget AMD A10 7850k APU builds. I love the case he chose to use (Fractal Node 304) and I thought the system was a very good choice for someone who wants to get into gaming on a budget with a clear future upgrade path. I may actually use the AMD A10 7850k APU in a budget build for my mom, since it will allow her to have acceptable graphics performance with 1080p movies and will do light gaming without having to buy a discrete graphics card.