This game is the sort of game that will get 'Puzzler' readers and Guardian crossword doers amused for hours on end.
The game starts off fairly basically with a vertical grid with some lines on it like in 'join the boxes'. You first have to travel over these lines to change their colour (whilst avoiding some meanies that are after you). When you have done this, it is time for the collapse. This is when you climb on one of the bridges and give it a nudge; this swings around, depending on how you nudged it, and knocks out another bridge, and so on in domino fashion.
Occasionally a bridge will have nothing else to knock out, and you have to go to another part of the bridge system to start again; however, the author says that on each screen there is a place that will knock out all the bridges in one fell swoop (and earn your lots of bonuses!). This is where you need your tame 'Puzzler' reader.
On the whole, a fun and puzzling game, though a bit on the simple side when it comes to gameplay, and I don't know how long the interest in it will last once you have played through a few screens.