Wurlitzers and Mellotrons and why should we care?

This is an odd first post, I know - but it's what I want to write about. Fair warning - I probably won't answer the "why should we care" part.

I just got back from Indiana where I had an opportunity to visit my grandparents. They recently moved into an assisted living center, lovingly dubbed "the prison" by my Grandmother. That aside, the place is really nice and they have a movie theater room which is really impressive. In one corner of the room I noticed a Wurlitzer electric piano and played around on it for a few minutes. (Using the internets and the googles, it looks like what we have on our hands is a Wurlitzer Orbit II Synthesizer). The Wurlitzer Orbit is apparently a pretty old - there isn't too much info out there on it. What I can say, having spent a few minutes tinkering with it, is that it is similar to a Mellotron in that it has the ability to synthesize different instruments.

The point of including synthesizers on these keyboards was probably to replace the actual instruments it was supposed to emulate (for instance, a flute or horn or chorus), but they sound so unlike the actual instruments that it isn't remotely feasible for use in a recording. What IS important is that these were some of the first synthesizers widely used and created new sounds when they weren't meant to, something that a lot of artists used to their advantage. Here's someone much greater than I explaining Mellotrons.

Some of the sounds created by these instruments have defined songs, such as:

Beatles - intro to Strawberry Fields Forever (Mellotron, obviously)
Beck - intro to Where It's At (Wurlitzer electric)
Marvin Gaye - I Heard It Through the Grapevine (Wurlitzer)
Neil Young - See The Sky About to Rain (Wurlitzer - through a Leslie speaker)
Supertramp - Logical Song (Wurlitzer)
Tom Petty - You Don't Know How It Feels (Wurlitzer - also through a Leslie)
Queen - You're My Best Friend (Wurlitzer)
Led Zeppelin - Kashmir and the Rain Song (Mellotron)
RHCP - Californication and Breaking the Girl (Mellotron)