I actually play a lot of Flash games. Because I spend a lot of my time at work on a computer, sometimes Flash games are the only thing to keep me entertained when it's a slow day. Like today! So, if you can't wait for the weekend to come, why not while your time away with Clockwords, a fantastic mashup of Tower Defence and Scrabble.
The game has a similar style to Professor Layton (at least, in the visuals) and is frenetic, challenging, and rewarding. Plus, it has insanely high production values for a free Flash game, so there's really no reason not to check it out. Be forewarned – you should have a couple of hours free before diving into this one.