Spongebob's Jellyfishin' Game is a Shockwave game found on Nick.com's site in 1999. At the time of release you would of gotten a free screensaver when you played the game.
UPDATE 01.03.16: The game was found, still on the Nick.com site, although that the game isn't listed on the site. Link: http://www.nick.com/games/data/spongebob/sb_jellyfish/SBjellyfishing.dcr