Every time you play your Sony PlayStation, Playstation 2 or Playstation 3, do you take a moment to say, "Thanks, Nintendo!"? You don't? Well you should, because it's unclear if it hadn't been for Nintendo's indecisiveness if the PlayStation would have ever been born.
When the Super Nintendo launched in 1991 (and in 1990 in Japan under the name Super Famicom), there was a mysterious port on the bottom of the unit that no one was quite sure what it was for. Over the next year or so rumors started coming out in the video game magazines that Nintendo was planning on releasing a CD-ROM peripheral for the next evolution in gaming, and to also make it so it didn't appear Sega was outclassing them with its Sega CD. (which would have been hard to do since the Sega CD sucked)
Nintendo began experimenting with CD-ROM technology, and it ended up turning to Sony for help with the possible expansion. It appears Sony proposed two possible solutions: an add-on to the current system, and a disc-based system that would also play the cartridges. Work began on a 16-bit CD drive the SNES/Super Famicom would sit on top of (that is the Super Famicom version pictured here), but while the disc system seemed to work, the SNES was having trouble handling processing the data.
With the 16-bit system just not coming to fruition, Nintendo decided to scrap it and start over with a 32-bit system. Sony was again included in the build process due to licensing issues, and a jumbled legal mess that also involved Philips trying to work with Nintendo on a CD-based system. The behind-the-scenes wranglings between the companies slowed development, but in May 1993, the technical specs for the SNES CD-Drive were finally announced and then … nothing.
Apparently Nintendo decided to start work on a whole new system, and Sony was unsure what to do with itself. The final fallout of this whole mess was that it was decided the SNES CPU simply couldn't handle the CD-based data, so all the companies decided to part ways, and Sony was left holding all of this hardware development in their lap, so what would you have done? They used that as the ground work for the PlayStation, and the rest, as they say, is history.
So, yes, you do actually owe a debt of gratitude to Nintendo for your Playstation fun, if it has been for them changing their minds constantly, and causing legal problems between multiple companies, who knows if Sony would have ever entered the video game business.