For me it was the free version of Cinema4D.
First I bought a HDD(600Mb) ,a CD-rom drive and finally the 030@50Mhz with 16Mb ram.blizzard1230mk3
A year or two later I got a cheap 040@25 card with amazing 32Mb of ram.blizzard1260
(got only the 040 model clocked at 25Mhz
Friends that have been with me in the computershop told me I'm nuts to buy such an expensive(~200€) crap for a dead and outdated system.
Lucky for me that I gave a shit on that.
Because looking back it was worth every cent...
Workbench was running like a charm. Many games where loading faster or even running faster(e.g.F1GP,Frontier) and Hdd access(even IDE) was much better.
Well - and WHDLoad on a stock amiga. Without me...
Today I thend to use an emulator for a quick game or two. Just because I'm a lazy old fart now.