I dunno - the last time I had a tetanus booster, my arm was swollen for about 2-3 days, and tender for about a week after that!!
It would take the threat of something before I volunteered for another one (damned college entrance requirements)
I feel pretty good though - seems my shot record is better than most - Hepatitis B, DPT regimen within last 5 years.
The only thing - I'm too young to have had smallpox vaccine
At least you know you're immune to the deadly germ.
If you didn't react at all, it would be questionable if you were really immune. When you get an immune response, you at least know that you're truly immunized.