There's nothing funny about high voltage electricity. The field strength is high - a 240kV high voltage grid line, 50 metres away, gives 4800V/m - but otherwise it's the same electricity that's in your house, much closer. The UK 240V supply would give the same field strength at 50mm, so if pylons make you feel ill, so should turning the light off. There is about ten times the field standing on the platform of a 25kV European railway.

The magnetic field from the lines is even less of a problem, as the high voltage means a correspondingly low current. A gigawatt transmission line at 500kV carries about 1500A per phase. The field diminishes with the square of distance, so 1500A 100m away is about the same as 15A 10m away, in other words the ordinary fields around your house.

The ELF restrictions proposed are really the result of massive lobbying from the neurotic and there is no evidence of effects at the level of exposure you get from electricity transmission.

On the other hand, as others have said, many people find pylon lines unsightly, and superstition has its effects - it might be easier to sell a "haunted" house.