I haven't had any truly terrifying ones, though when I was tearing apart my parts car last year I came face to face with a couple brown recluse spiders which was a bit unnerving. That was while tearing it down to the firewall, which was not a very fun job. (The car and spiders are long gone now though!)

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth