I’m using a 2012 11" MBA - that I bought after DHH kept tweeting about his - and fell in love with it.
I’ve tried others, such as a 15" MBP, 27" iMac etc but the MBP was just too big and I wasn’t fussed on the iMac (My main machine prior to the MBA was a Mac Pro). The MBA is so petit, so portable, it’s the most personal personal computer I have owned and I am quite attached to it. When it’s in it’s cute little sleeve, I look at it and think - this little thing can change the world, bring down govts etc etc etc
So my (somewhat feasible in foreseeable future) dream computer is a MBA of or around the same size but with 6 or 8 cores and an onboard GPU, 1TB HD, 64GB Ram and with a Retina display and 4 USB-C/TB ports.
My next (main) computer might actually be a 6-core Mac Mini, it has good IO with 4TB ports so you can add an eGPU, fast SSDs and even upgrade the RAM yourself. Just kinda interesting as I like tinkering I also have an LG 5K monitor here which I bought when Apple introduced it at a cut price, so they would pair nicely.
Funnily enough my MBA crashed today and then wouldn’t boot back up - it’s NEVER done that before I hope it’s not dying