One of the things books always say about dreaming is that for some reason the act of reading is challenging in a dream. I.e. one way to realize you're dreaming is to try to read something, then re-read it. For some reason the brain never has the words stay the same. So that's a great test to do to help you become conscious in a dream.
Last night I had a dream that I was trying to show a friend a video of my boyfriend's band. So I was trying to look up the video name from a bunch of DVDs. Every time I went through the DVDs, though, the names would change around and I'd lose track of what I was trying to play. Finally I got frustrated and started taking every other DVD out of the pile and putting them elsewhere so I would be left with one and only one DVD. That way I'd know it was the right one.
I should of course have realized I was dreaming, if this bizarre word-changing stuff was going on
I used to be more active in dream studying and when I was, the word changing would have instantly snapped me into consciousness. I would have known I was dreaming. But because I've not been practicing in a while, my mind just accepted it as normal that the words were changing randomly.
I'll have to put fresh effort into paying attention to this, so next time I can be lucid!
Do you ever try re-reading things in dreams, to see what happens?