Frabjous means "wonderful or delightful," and you might use it to describe the feeling of winning the lottery. But then you'd have to deal with taxes, which most people find less than delightful.
The word frabjous comes from Lewis Carroll's poem "Jabberwocky," included in his novel Through the Looking-Glass, the sequel to Alice in Wonderland. The word is first used when the hero triumphantly kills the terrifying Jabberwock, and it looks like words such as fabulous, joyous, and possibly fair, so people started using it to mean "extremely good." Carroll coined a bunch of other words in the same poem including galumph, chortle, and burble. How frabjous!