$650 for a 2408WFP is a big jump, although it is a great screen.
If you can still find it, the Gateway FPD2485W (discontinued) uses the same S-PVA panel as the older 2407WFP, but with inferior electronics (it is more prone to banding in gradients, but not noticeable outside of artificial scenarios). I got mine for ~$450 with a speaker bar (Mmm...tinny).
Otherwise, the Westinghouse L2410NM uses a MVA matrix and is a steal at $410. Haven't seen it in person, but some people online seem to be pretty happy with it.
If you really can't fit a 24in, the Ultrasharp 2007W is a very nice display, but at $399 it's the same price as the Westinghouse. It's also being discontinued, though, so don't wait too long.
I'd really recommend a 24in screen though, since it's typically the minimum screen size that is full HD+ (1920x1200). Can't clear any desk/cubbyhole space?
Wind, Sand and Stars.