You can get a EUR 9 discount off the EUR 39 full price if you buy your Restopass online and enter the following code: VIP-637. (Thanks to the reader who sent this over!)
Hurry up – the code is only good until next Wednesday (15 September).
Note: Restopass is a booklet listing 40 popular user-recommended restaurants in Brussels. The pass allows you to get a 30% off each of those restaurants (to be used once, only on food, and with a maximum discount of EUR 50 per restaurant). Read more in this older post. I used it in the past and it is a good deal – you generally already get your money back and start saving after the second use.