Happy Birthday Spectrum!
My top five is a bit skewed, as my favourite three were all made by the same guy...
1. Laser Squad (yeah, I've mentioned it a few times
)
2. Rebelstar (loved all three versions of this, Rebelstar, Rebelstar Raiders, and Rebelstar 2)
3. Lords of Chaos (this was the sequel to the Chaos game Kieron mentioned - though I did love the original too)
4. Bubble Bobble (spent forever on this, playing two-player with my brother. Never did complete it, though we did get to the final level a few times.)
5. Elite (damn but I got through reams of paper playing this, scribbling down prices of goods etc.)
Honourable mentions to the following, in no particular order, who didn't quite make the top five:
Hypersports (loved it, but was responsible for the destruction of umpteen joysticks)
Monty on the Run (enjoyed most of the Monty Mole games, but "on the Run" was definitely my favourite)
Tetris (I've probably spent more time playing Tetris than any other game, if you count all the different platforms I've played it on)
Wheelie (never did find out why I'm trapped in a cave with a motorbike, but I had a lot of fun trying to escape!)
and most of the Dizzy games.