Precalculated periods sums
Steve Atkins at Multibase sent me this interesting link of some slides from OpenERP Spain community days. A topic which has been hot in the Australia / NZ localisation community.
http://www.kami.es/es/blog/2011/4/18/acelerando-contabilidad-openerp-sumas-precalculadas
The site is in Spanish but the presentation is in English and well worth a look.