There is an interesting whitepaper available - SOLID STATE DRIVES IN HIGH PERFORMANCE COMPUTING REDUCING THE I/O BOTTLENECK. It elaborates the usage of solid state disks in high perfomance computing:

Use of SSDs with Sun servers and blades has demonstrated significant performance improvements in single-system runs of FEA HPC application benchmarks, and through the use of the Lustre parallel file system. There is significant promise that other applications with similar data throughput needs and workloads will also obtain increased bandwidth as well as a reduction in run times.