I shut down my company (Stage, heystage.com) back in December. It feels silly to keep renewing the domain, but it also feels silly to let it lapse; since only one of those decisions is reversible, I'm paying to renew it.
What should I do with the .com of a now-shuttered business?
Keep it just for the email addresses and accounts you may have opened using those email addresses. If you don't, there'll be something you've missed and you won't find out for 6 months. But drop the website.
I have a number of zombie domains that I keep just for that reason.
If you have any accounts on the domain, then yeah probably keep. That's what I'd do at least.
Zombie businesses don’t make bootie calls. Let it go and move on. Good luck.
DHH may buy it :-)
Keep it - Costs you less than $20 a year, might give you good (or cautionary) memories, and one day someone might want to buy it off you for real money.