very hard to create from scratch.. i've used Clip Share and, so far it works great.
where it really gets hard is if you want to venture into the HiDef world.. that requires a lot of installation at the server side. just assuming that one downloads mplayer/mencoder/ffmpeg, grabs some audio and video codecs via RPM or YUM ain't gonna cut it if you want to do it right..
then you run into the whole font overlays and getting that part to work for text ads etc..
i found that the Nero Encoder is the best for hidef, versus the h.264 one that you can find tutorials about on the web..
too many subtle things to check and also you have to solve the video upload issue where you have to open up the max_post_size and stuff like that to accept large videos to be encoded in the background..
after you get it working, then you also need to decide on a good player. mplayer is ok, but there are better ones out there.. (i recommend nuevo player)
bla bla bla.. but its not for the faint of heart, nor is it easy to just upload a wmv and 'it works!'
http://hsoshow.com/video/41/Click-HD-and-Full-Size--Caves-and-Ancient-Life is an example of a nice HD video with the player skinned to the customer's liking.. it took me longer than i wanted to get it right, but in the end, it can be a good thing...
that project is still on-going with the next/final part to integrate the user DB from both softwares.. clip-share to/from ubbthreads.
just to reiterate.. it's not a small task and using 'free stuff' out there prolly won't do you any better than just using YouTube and embedding from there
