I've tried riding once without glasses....It sucked. Ridden a couple of times without a helmet. It was rather nice not having the extra weight on my head. Like I said though, for me it would depend on how far I'm going. 1 mile round trip, no helmet. To work and back (roughly 25 miles round trip), I'd wear one.

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"BOY: On a hot summer night, would you offer your throat to the wolf with the red roses? GIRL: Will he offer me his mouth? BOY: Yes. GIRL: Will he offer me his teeth? BOY: Yes. GIRL: Will he offer me his jaws? BOY: Yes. GIRL: Will he offer me his hunger? BOY: Yes. GIRL: Again, will he offer me his hunger? BOY: Yes! GIRL: Yes. BOY: On a hot summer night, would you offer your throat to the wolf with the red roses? GIRL: Yes. BOY: I bet you say that to all the boys!" -Meatloaf