Although we went through a period thinking we have an abundance of CPU power, efficiency is back in vogue as it's needed everywhere from the mobile, because of limited cpu/battery, to servers trying to solve the the C10K problem (serving >10K simultaneous connections).
Couple of interesting projects are the Redis server, written in tight ANSI C, and the Go language, kinda like a combination of C++ and python with a nod towards erlang.
Redis is an advanced key-value store. It is similar to memcached but the dataset is not volatile, and values can be strings, exactly like in memcached, but also lists, sets, and ordered sets. All this data types can be manipulated with atomic operations to push/pop elements, add/remove elements, perform server side union, intersection, difference between sets, and so forth. Redis supports different kind of sorting abilities.