Get a controller like the new rev of Arturia KeyLab MK2, Native Instruments Komplete Kontrol, etc. and do your synth learning in software.
You'll not only get your fix, but you can get a big old bag of synths in the Arturia V Collection 6 for a few hundred bucks and have the experience of your DX7, Jupiter, Buchla, CMI Fairlight, Moog, ARP, Synclavier, Prophet, CS-80, Solina, etc. and entertain yourself for an eternity.
Would I ever need or buy a Buchla Easel? Of course not. Is it hella lotta fun to have this in software. Yes it is! And for the price of my beer money.
Yamaha U1 Upright, Kurzweil Forte 7, Viscount Legend Live, Roland FA-07, Native Instruments Komplete Kontrol S61 Mk2, Arturia V Collection 6, Komplete 12, Lots of iPad Stuff, Pair of QSC K10 Speakers