The NBC website has a page called NBC Rewind where they stream full episodes of many of their shows. Usually, they only have one up at a time but at the moment, there are several episodes up of each of several series. The site doesn't seem to run smoothly (neither does NBC) but I did get a couple of the videos to play on my computer, especially when I gave up on Internet Explorer and tried accessing it via Firefox.
This link will take you to the menu where you can pick something to watch if you're so inclined. A couple of folks have written to ask me where they could see Stan Lee's appearance last week on the game show, Identity. Well, you can see it here. Look for Thursday and then look for the second part of the show. The portion with Stan commences a few minutes in.