Don't regret the good times for one second, but do get very jealous of people on HN talking about all the exciting tech they're using and awesome work environment. I am actively taking steps to move to a better company, but my god I'm finding Cracking The Interview Code a slog.
Same here...and then add on that I'm actually over 40...and oh boy, does that code get tougher to track. Funny how in some circles deep and long experience in tech is respected...but companies often look at me and ask "What will you do for me lately?"...and look at my age, and likely assume that I'm slowing down; when just the opposite is happening, i'm speeding up in terms of complexity of tech i'm diving into. Weird; but i feel your pain!