Twitter has one I learned recently, but it's pretty enfeebled. It's as far as I can tell, exact matches only, which sounds fine perhaps in the design phase, but

Twitter has one I learned recently, but it's pretty enfeebled. It's as far as I can tell, exact matches only, which sounds fine perhaps in the design phase, but was deeply frustrating in practice. There's a new political candidate in America generating lots of buzz who has several permutations of their name (abbreviations and hyphens were my undoing here), so I ended up having to add several entries just to not hear about politics in a country I don't live in!