I've been in this game a long time but there is still nothing sweeter than launching a site after spending a months building it with your team and the client. As a TD, site launch brings a mix of emotion - fatigue from the lack of sleep for the 10 days prior to launch, relief that the site is launching on time and on budget and the client seems happy with it all and finally worry about whether the thing will work as expected, what will everyone else think about it and by god I hope the server doesn't fall over on Day 1 under load...
My grandfather was an engineer for Philips and he described to me the same feelings when they were launching a new product so I have a sense that irrespective of discipline, team based endeavours in engineering always foster the same heady mix of emotion fuelled by relief, adrenaline and fatigue.
Whilst I am an old hand at this within this industry these days, having been here since the dawning, it is great to watch members of the team for whom this is the first of many site launches in their career and their happiness that it is done and their complete pride in their work.
Having seen photos of workers completing railways and other major constructions in the 19th and early 20th century one can't help notice the parallels of young engineers completing a job regardless of whether they are working with steel, glass or lines of code.
Source for citation: ajfisher.me/2008/01/08/the-warm-glow-of-site-launch.