I only discovered Ibanez as of the early 1990's, so I imagine plenty of people are going to disagree with me here...
1) Iceman bass. Because it is so metal.
2) "Ivy," my SR-300 in Green Metal Flake. Because I can't think of a more intelligently-designed, better-crafted modern bass for under $300. She does almost everything I need her to do (except Low B, and "vintage" Fender/Gibson/Rickenbacker tones, but that's what I have my P-bass for), and more.
3) The BTB series basses, because the market needed affordable 5-string and 6-string basses that were designed from the ground up to be extended-range instruments.
4) The Ergodyne "EDA" bass from the late 1990's and early 2000's. Because it looked sexy in "Vampire's Kiss," and was pretty innovative for its day.
5) The Eagle bass of Ibanez' early days. Because if Krist Novoselic plays it, it has to be awesome.