Okay... maybe there is some cyber-ectoplasm after all! Well... ghosts are weird... they're supposedly formless and devoid of matter, yet they can sometimes physically interact with the universe (e.g. poltergeists). So perhaps a Spark is like that - formless yet somehow still able to be physically interactive. Yeah, it makes no sense... but let's face it, we're talking about freakin' spirits and Transformer spirituality here. Trying to apply logic here is like bashing your head against a brick wall. You just have to suspend disbelief and accept it really (remembering that spiritual beliefs are based on faith rather than empirical logic).

Who ya gonna call?