BTC Twitter Sentiment - shows the total numbers of all negative, neutral and positive Bitcoin related tweets.
On default settings, the tweets are plotted in red (negative) white (neutral) as well as green (positive). The three charts are stacked so the total number of tweets is easily discernible.
Furthermore, there's an optional smoothing setting in the options.
The Twitter Sentiment data is provided daily by IntoTheBlock; Since data is only updated once a day the graph might look chunky on lower timeframes, even with smoothing.