First there was a K-9 spin-off - in about 1981, originally - but the latest K-9 Adventures seem to have gone very quiet just lately. (Probably because no-one recognised the tin dog.)
Then there was Billie Piper: Earth Defence, which died a death when Billie didn't want to do it. Duh!
Now, Sarah Jane Smith (who was also in the original K-9 spin-off, of course) is going to battle evil with a 13-year-old neighbour for CBBC.
But most importantly, coming very soon (to me, at least :p ) is Torchwood, a proper grown-up spin-off, which sounds a bit like the X-Files filmed in Wales.
And in other news, Buffy Season 8 is set to arrive in March. Hooray! Er, but only in comic book form. Hooray, sort of.
Until then, it's endless Doctor Who reruns and Angel on DVD for me...