Top 10 worst toys for 2005: "What do dolls and ponies have in common with crossbows and energy beam blasters? They're all toys that have the potential to cause childhood injuries, or even death, according to an organization advocating toy safety."
See also the handy picture chart. Some of the suspects are surprising, but perhaps Anti-Gravity Boots, as a rule, are not a good idea. Or, get the kid a book.