As of January 2006....
(Figures are before tax, and include Basic pay and trip pay based on working 50 trips per year).
JNR cabin crew: £13,222.
SNR cabin crew: £15,515.
Cabin Service Supervisor: £20,259.
Flight Service Manager: £25,222.
Inflight Beauty Therapist: £16,132.
You can work on a rough guide of earning £300 - £600 per month extra on top of those figures in allowances (paid tax free in local currency).
Plus a little bit for commission, delay pay, under crew complement pay etc...
Hope this helps, I wish someone had been able to tell me all this before I joined the company!