Crosswords - some really original examples

I guess, many people like to solve crosswords (and their varieties) when they have a plenty of time to kill (for example, you're traveling by train or are queuing, or just have a lot of time at night...). They say that the first crossword was invented by the famous Russian writer, the author of notorious "Lolita", Vladimir Nabokov. Since that, this kind of riddles has become really popular and now we have a great number of crossword varieties, such as "scanwords" (Scandinavian crosswords), "chainwords" (when the following word begins with the last letter of the previous one, forming a chain of words) etc. You can find crosswords on the last page of a newspaper or a magazine, and the whole magazines of word riddles can be found everywhere. I think, inventing and compiling of a crossword is the equal intellectual fun. Sometimes you can even find crosswords to occupy your mind with on, say, bus stops or drawn on the wall of an ordinary apartment block. Here are unusual crosswords I've found. They look like traditional ones, but they are nevertheless original.

In 1998 the artist Anton Olshvang used to hang paper sheets with this crossword printed on them at bus stops in Samara, Russia. People waiting for their bus tried to solve it but they always failed to do that. It's not surprising, because Anton had given them a difficult task - there are no words matching to these definitions! You can try to solve this crossword yourself and you'll see that it's just impossible!

Horizontally:

1. Secretly glued dishes. 6. The surprise which is known beforehand. 7. Someone who's missed his or her train or flight. 9. Old insect. 11. The minute before the date. 12. The apartment full of furniture. 13. Unheard alarm clock. 20. The overgrown weed. 21. Grown-up legs. 22. The item hidden in time. 23. The unknown word. 24. The chair which can be turned only clockwise. 26. Two hundred grams of cheese. 30. The unpleasant TV show. 31. A continuous, repetitive sound. 32. The girlfriend's dress. 33. Minimal sovereignty. 34. The food left behind in a fridge. 25. The favorite work carried out on the daily basis.

Vertically:

2. The action which stimulates decision-making. 3. Erased wallpaper. 4. The petty violence of the road traffic. 5. The side opinion. 8. The feeling of social inequality. 10. Pure, but non-transparent water. 14. The sweater which is to put on upside down. 15. The scientific discovery deprived of emotional coloring. 15. The side of a knife which is not sharp. 17. Ink stains in a pocket. 18. Dust in unapproachable places. 19. The old duvet. 25. The empty roller. 27. The good habit. 28. Experience in writing poetry. 29. The absolute material value. 

This crossword can make you feel stupid and ignorant, can't it? But it's actually invented as a kind of mockery, so Anton Olshvang is sometimes called "the first virtual troll". 

Sometimes crosswords can be a landmark. Imagine a dull, grey apartment block which is a real sight to look at the city suburbs. It's quite difficult, isn't it? But Lvov (Ukraine) can boast of such landmark.

This stylish, ancient city has a wonderful "crossword house" in its "sleeping district" full of standard, dull multi-storeyed apartment blocks. The crossword is not just a decoration - you can actually solve it. Booklets with tasks can be found nearby. You can check your answers at night when the wall is lit by lamps and letters appear in grids. The topic of this enormous crossword - names of famous artists and architects.