Does anyone keep a Reading Log.../Journal?

I bought one from Indigo Books a few years ago, and since then I have had to buy a few more and a few more, I read so fast that I fill them up in a few months sometimes in only a few weeks! Dependng on how big they are. I keep a small one in my handbag at all times with just a list of books I have read each month so I have it on hand all the time :) Plus at the back of it I list new books I want to buy or read, it depends how fast the library gets new books in sometimes I just can't wait to read a book and I give in and buy it no matter what the cost, (Thank goodness for credit cards ) LOL!
The bigger reading log/journals I make comments in similar to my posts here, about the Authors and then comments on if I liked the book.