So, do you like to do brain challenges in your free time?
I do, I like to do brain challenges such as sudokus, crosswords, and many others (You mightn'd know the others, so i won't list them).
And yes, I am a bit of a geek.

I take working out my body pretty seriously, I do it at least once a week for a total of 12 hours a week. I also try to work out my brain as often as possible too, since that's even more important. Over the past few years I've been playing various brain games almost weekly (until recently, been busy with baby, website, freelance work, etc). Games I play include:
-Brain Age
-Big Brain Academy
-Brain Age 2
-Brain Challenge

They have a lot of different "brain workouts", ranging from Visual/Observation workouts, Logic Workouts, Memory Workouts, Math Workouts, etc. Someone can definitely raise their overall IQ by exercising their brain often and I'm quite surprised that more people don't do stuff like this and I'm even more surprised that schools don't focus on this stuff at all.

I've been tested with an IQ of around 156 and that's all thanks to the many years I've spent playing Video Games, Puzzle games, Brain games and simply eating the right foods that make a brain sharper (such as Omega-3/DHA).

I like to play word searches, if they're considered brain challenges. I also like some of the more easy sudoku puzzles but I'm terrible at the harder ones.

sometimes i do because I'm in french immersion i really need to if i don't I'm in trouble then lol
french vocabulary
dictation and such

Every once in a while I'll try to do a crossword or a word jumble, but I do Sudoko quite often and I enjoy testing myself on very challenging ones. I'm not to good at crosswords though and I usually quit half way through because my vocabulary is not very "expansive".

It's great to see so many people like to exercise their mind. May I recommend the next time you go to a newsagent, consider buying a crossword book or something. It won't do you any harm.

I do it sometimes.

Not too much, because I'm usually using all my time for homework and projects, etc.

I like chess, and I do sudoku puzzles once in a while.

I like to play word searches and cross words whenever I can

Oh yes. I LOVE playing around with crossword and sudoku puzzles. And once in a while I pop in Brain Age for the DS.

Every once in a while with a video game or online game I'll do a brain challenge.

I do when I get bored, it is fun to do something that gets your brain working