Most valuable crop per unit area?

Are their any websites that indicate this as i want to get the most out of my allotment as possible (125sq/m)

any suggestions?

It would be foolish to grow anything at a financial loss over the long term, but also daft to grow things you don't like just because they are financially "rewarding."

Runner beans would top my value per square foot table, and courgettes are never cheap..............

I don't know of a website that does both yield and value (it would be a pretty subjective analysis) but the following very recent post includes a link to some yield information.

http://chat.allotment-garden.org/index.php?topic=66130.msg755313#msg755313

Here is another one which might make your calculations a bit easier but bear in mind it is based on US conditions which will almost certainly differ from yours:

http://usagardener.com/breaking_ground/plan_a_vegetable_garden.php

This is virtually a repeat of what was said in your other question here:

http://chat.allotment-garden.org/index.php?topic=66130.msg755184#msg755184

For once we're consistent with the answers!

Baby salad is a good valuable crop such as mixed salad, lettuce, spinach, mustards, pak choi, watercress etc. Over a quid for a small plastic bag in the supermarkets. Sow every fortnight or so from Spring through to Autumn and assuming you like salad you will save a fortune. Raddish and cucumber are also good money savers. Helps if you have a cold greenhouse, polytunnel or cloches in early spring / late autumn. Great to grow in containers.