Horse fly (Diptera: Tabanidae), possibly Tabanus bovinus, in Värmland, Sweden. This large (1.7 cm long) fly has very large eyes that defract light. When they die they lose these beautiful colors. It is commonly found in my car since it probably is attracted to CO₂ from my breath and probably by the warmth within due to sun heating (the fly may think there is a horse, cow or human inside because we are warm-blooded and radiate heat). Note the piercing mouthparts protruding in front of the eyes. It takes a few seconds to pierce your skin and they seem not to be able (or want) to stab you will holding them. They will buzz like a bee to try and scare you (most syrphids will do this also). The are very good flyers and are not caught by the robber flies generally.

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Images © 1996 by John A. Byers, Chemical Ecology.