A friend of mine has recently started a research group. As usual with these things, she is on a shoestring budget and has computational demands. The computational task is very parallel (but implementing it on GPUs is an open research problem and not the topic of research), and very CPU bound.
Can slashdotters advise on a practical way of getting really high bang for buck? The budget is about 4000 GBP (excluding VAT/sales tax), though it is likely that the system will be expanded later.
The computers will probably end up running a boring Linux distro and Sun GridEngine to manage batch processing (with home directories shared over NFS?).