As we're sitting like nearly all day, my sit is like dead.. I was wondering if some (tall) people have recommendation about good sit ?

I'm not living US so please, don't give me Walmart references. :p

Thanks

Go to walmart and buy... Oh wait

Well granted I am not tall, but I know there are special chairs which are optimized for your back. You may want to see a back specialist for that, but secondly you can also consider using a standing desk as sitting in general is extremely unhealthy

Herman Miller Aeron.

Try getting a monitor stand to rise up the monitor as well so you don't slouch to see the screen.

Thanks already for your advises guys ;)