Goddam gooeys (GUIs). What I do for a living (primarily) is hack^H^H^H^Hmodify payroll programs (it is not nearly as glamorous as it sounds). Secondarily, I work with Financials (G/L, A/R, A/P) and distribution (Sales Order Entry, Purchase Order Entry, Warehouse Inventory, etc.). Look at the input documents for any of these systems. They are text based. There is no reason in the world to have a GUI for a system that is text oriented. I have my theory as to the preponderance of GUI (and gooey's intimate cousin, client/server) in the last decade. Two I.S. Directors  are out playing golf. One says to the other "my system is gooey" (or client/server or configurably networked or ...). The other director runs back to the office, calls a meeting, and while thinking "ohmigod, how embarrassing, our system isn't buzzword compliant" tells his people "here is my vision for the future of I.S.". As a result of this a perfectly good system (debugged, users trained, possibly even written in house) is replaced by some shrink-wrap monstrosity with less functionality than the current one, necessitating huge capital expenditures on things like fibermuxing and servers and client/server DBMSs and color monitors that not only do nothing to make the individual users (always, in my mind, an A/P clerk) more productive, but probably actually hamstrings them.
And I haven't even gotten into how I feel about mice. What a waste. I resent, bitterly, every time I have to take my hands off the keyboard. The little point doohickey on my ThinkPad is tolerable, but only just barely. But I am not a data entry clerk. For my apocryphal A/P clerk, every time s/h/it has to remove a hand from the keyboard to touch a mouse, transactions per hour has just gone to hell. Now if you're an engineer working with CAD or an artist working with photoshop mice make sense (as does a GUI), but not for a data entry clerk. The mouse is nothing but a destroyer of productivity (and an ergonomic nightmare).
Peeve: Windows/GUI, etc. killed Clipper, which was a very adequate business application development language (actually a C generator). Windows isn't an operating system. It can't be. Where is the fucking command line? But people see a DOS based text application and they can't see the functionality, just the fact that it isn't windows. What good is windows anyway. I spend 95% of my time (on a PC) in just three applications , and they all (or their functional equivalents) could run just as well under DOS.
 Long ago my boss was a D.P. (data processing) manager. I wonder if such a thing still exists. Information Services is bullshit, assholes who got MBAs without ever learning how to program.
 Word (which I don't like as much as the WordStar which ran on my mom's CP/M Kaypro), e-mail, and Quake (which I run in DOS-mode anyway). This, by the way, was composed in Notepad. I'd've been just as happy in MS-DOS edit.