Have had the chance of working 18 month with NeXT computer - best (spirit) of machine ever... Improv was outstanding, but too much so... people couldn't easily adapt their spreadsheet work to the new tools (and on NeXT, in a time when green screen PCs here trying to adopt Windows 3.11 ;-) ) - seen quite a few applications never used to their potential benefits (and just wither away, replaced by less capable partial imitations)