I think whatever makes your day to day life better and more exciting, makes you day to day job as a developer easier too.
But that's not an easy thing to achieve in my opinion and it's directly related to your personality and how you're living your life. Everything else - a new keyboard, a brand new iMac, flowers - is just a distraction, for you to escape from finding that ultimate happiness. I haven't found it yet. Fingers crossed that will find it eventually but until then, I think it'd be loads of puzzles and features and "distractions" that can make my day-to-day life as a developer easier. Oh, this and a Spotify that knows me so good that I don't need to skip any more songs ever again.