tiny pink flowers

There's a plant I found growing in a pot that I can't identify- could someone help please? The body looks a lot like rosemary or lavender, those kind of thin leaves, and the longest stem is a good two feet tall. It's just blossomed, and has a "spike" of small pale-pink flowers which look trefoil or orchid-like. There's no scent I can detect.

I'd be grateful for any ideas on this. Is it A Good Thing, or should I be ripping it out, burning it and dancing on the ashes?

Sorry about the terrible photos, it's getting dark! (Cameo by my beloved fuchsia, several corn marigolds and a pair of strawberries :hehe: )

 

Looks like Linaria purpurea Canon Went. Common name Toadflax.
It seeds around, but I love it and am very happy to have it.

http://www.google.co.uk/images?hl=en&rls=p,com.microsoft:en-gb:IE-ContextMenu&rlz=1I7SUNA_en-GB&q=Linaria%20Canon%20Went&um=1&ie=UTF-8&source=og&sa=N&tab=wi&biw=1255&bih=537

It is the pink form of Linaria purpurea.

http://www.wildchicken.com/nature/garden/nature_200_146.htm

There is also a white flowered form called Linaria purpurea Springside white.
http://www.bethchatto.co.uk/plant portraits l/linaria purpurea 'springside white'.html

 

That's the stuff! Lovely, thanks. I think I'll keep it! :