I think its possible to use a Classic Amiga for modern work assuming you have two things:
- Upgraded hardware (ie. Accelerator, Memory, Networking and Gfx card).
- Latest OS Software.
I've set up an emulated A4000 w/UAE gfx at 1280x720 resolution with the following software:
- ClassicWB + OS3.1
- MUI 4.0
- Wordworth 7 (word processing)
- DPaint 5 (graphics)
- Pagestream 3 (desktop publishing)
- Netsurf 3.5 (browser)
- AmigaAMP (music player)
- MicroGoldEd (text editor)
- Storm C 3.0 (if you do C development)
- YAM (mail client, in case you don't like GMail web interface)
- AmigaSAMBA (file sharing with other computers on my network!)
- DOpus 4 (file manager)
With the above software, you can actually get along quite nicely and have usable equivalents for everything you would do on a modern PC. Netsurf 3.5 browser is what really makes this shine, as we finally have a modern browser for classic systems. I'm using 256 MB of fast ram and have no problems multitasking and everyday usage, but you could get by with less (probably at least 32-64MB).
I'd imagine a real Amiga classic with at least 64MB ram, accelerator (68040+ or above) and gfx would actually be a usable machine even in 2016.