Book recs?

I have £50 to spend on Amazon, and as I bought most of my academic books last term (which might partly explain my current destitution), I am going to spend it on things I want to read (though if only I could remember what that very good feminist book about the symbolism of John's Gospel was called, I might buy that, but like a moron I lost the bit of paper I wrote the title down on...)

However, I am being paralysed by the available choice. £10 is going on season 4 of DS9 (Lawyer is buying S3, and may I point out how fabulously cheap the box sets currently are on Amazon?), but I find myself at a loss as to what else to go for.

Help me, internets, you're my only hope! Otherwise I will end up doing something stupid like buying the Summa of the Summa...