I've had a read through the other threads related to this issue but I haven't come across anything remotely as extreme as what's happening with my N900.

Today for example, at 2pm my phone was fully charged with green light. At 8pm my phone was dead.

In this time my only phone usage was sending one text message, receiving one 10 minute call and accessing about 6 web pages through the maemo browser.

I'm pulling my hair out at this point.

I have the current firmware installed, no apps that particularly drain power. No power kernel installed and it's not overclocked.

I would be most grateful if anyone could share some advice.

You could try replacing the battery to know if the fault is from the battery itself.

Please search forum for (tons of) advices about using top and powertop for filtering problems relating something eating CPU cycles/battery and/or battery faults.

Otherwise, Your reports is just plain lacking any useful data to help You with your problem.

/Estel

I replaced the battery about 2 months ago.

What programs for monitoring battery/cpu usage would be best?

batterygraph

I've written already - top and powertop.

/Estel

If it's a fake battery it is possible that it's gone nad in two months. Does the device heat? If not I would place my bet on a faulty battery. If yes something is draining power