Since it's Valentine's day today, let's write a love letter to our favorite software :)<p>I'll start: Postgres - there's nothing this workhorse can't do and it keeps getting better. Also, it has never let me down.
xBASE (dBASE derivatives). I did lots of "table oriented programming" experiments with it. It's essentially a semi-relational "tabular scripting language" with lots of meta ability so tables can be used to generate other tables, and it's easy to put code in tables and vice versa. Table-driven UI's were also looking bright.<p>I wish there were an open-source dynamic interactive version out there (Harbor is compiled). It fell out of favor largely because it didn't scale well to "enterprise" projects, and couldn't gain OOP fast enough, but for small-group apps and ad-hoc data fiddling, it was wonderful.<p>Yes, it had warts, but all tools do, and many solvable if not tossed away. There's nothing common like it. RDBMS-based products are too stiff and verbose. If Lisp is "everything is a list", xBase was close to "everything is a table". It's kind of half APL and half RDBMS.<p>Hearts!
Postgres is indeed a very good choice, I know I can always count on it.<p>If I had to choose one, I would go with Emacs. It is not perfect of course; if only it was written in Common Lisp. But it gives me a huge amount of control on everything I use it with: programming, notes (Org), mails (Gnus), and so many other things.<p>No other software is that customizable.