I love those side-on illustrations Red Bull! I've always wanted to do things like that, I tried doing some for my rfactor league a while ago but couldn't shade them very well. I've recently discovered the wonderful Gradient Mesh tool...that has changed my illustrating life! (..just noticed you've used photoshop so you probably don't know what im going on about lol)
The McLaren pitstop illustration looks great too, I know what you mean about getting bored half-way through. I worked on the Raikkonen pitstop one on and off for a year, and I have loads of ones that I just haven't bothered finishing (or barely started).
Webber Fan: that webber pic is awesome :D
I've been working on another pitstop illustration, this time one of Alonso, nearly finished it after 6 months so I'll post it here once it's done.
Ric Scott