http://dictionary.reference.com/search?q=gaygay (g)
adj. gay·er, gay·est
Of, relating to, or having a sexual orientation to persons of the same sex.
Showing or characterized by cheerfulness and lighthearted excitement; merry.
Bright or lively, especially in color: a gay, sunny room.
Given to social pleasures.
Dissolute; licentious.
n.
A person whose sexual orientation is to persons of the same sex.
A man whose sexual orientation is to men: an alliance of gays and lesbians.
[Middle English gai, lighthearted, brightly colored, from Old French, possibly of Germanic origin.]
So, since it's being used as an adjective let's see...
Nope, Boing Ball has no sexual conotation or is a person.
Cheerfulness and lighthearted excitement, hmm, Depends on you perspective at the moment I guess.
Bright and lively in color, I can see that.
The rest of the definition doesn't seem to apply.
So, Yes, The Amiga Boing Ball could be considered gay.