While the big jets were an interesting target for me at Boeing Field, there is a good trade in smaller corporate jets too. The regularity of Citations and their ilk makes them a little less exciting but they can still be interesting if painted up nicely. However, one that caught my eye was an older Learjet. This is operated by Boeing Flight Test as a support and chase aircraft for their programs. It taxied by before departing over my location.
Also we got a Dassault Falcon 10. Quite a vintage type of jet these days so that was a nice surprise.