Yay for spamming up this thread, but look what I did this afternoon as an experiment. :P Someone had to do it eventually I guess and I appear to have the aptitude, so...
Freeman's Mind in Black Mesa Source, Part 01 & 02
If it's popular enough or if nobody else does this better than I can (or if I don't get told by Ross Scott or the BMS team to stop), then I'll continue with more episodes. It'll be just clips like this though, and only with scenes that work with the dialogue, due to how different Black Mesa is from Half-Life: Source.