Many, many pieces of electronic music, for the BBC and otherwise. I don't expect you to actually read this, but a lot of her work is covered
here. You might want to just skim it -- she's done a
lot.
EDIT: To make things easier, you can use your browser's Find feature to skim the page for references to "Delia," as that's how she's most commonly referred to on that site. As I said, you'll see quite a bit. (The person on the site seems to be, well, not the biggest Doctor Who fan. But it's still a good reference for Delia's work.
EDIT #2: If you are interested in Delia Derbyshire, you may visit her web site here. DO NOT click the link at the bottom of the page I linked to above -- that leads to DeliaDerbyshire.org, without a hyphen between. The domain name for that site expired, and was renewed by some unspeakably despicable lowlife who replaced it with a rape pornography site. Absolutely disgusting; like spitting on Delia Derbyshire's grave. I just wanted to note that in case you were tempted to click the link.
I like how they say: "There's also Delia's original Doctor Who theme of 1963, but reviewing that now is rather like reviewing, say, "My Generation" on a compilation of The Who; it's not that it's bad, it's just pointless considering its status as a cultural cliche and how much fascinating material there is surrounding it."
