This is fairly high-level play (not high CL, obviously, but high optimization level). An alternative to Red Wizard is Archmage, which gives you SLA's - combine with Arcane Disciple (Luck) and you've got yourself SLA's of Miracle to have fun with, which gets you among other things, Greater Consumptive Field or Body Outside Body which works if your DM rules against having two regional requirements. Only downside is you cannot ban Evocation in such a case (but that's not necessarily such a bad thing, you get access to neat-o things like Contingent spells (although why a high OP caster doesn't have Craft Contingent anyway, I'll never know).
At slightly lower levels, this falls to 5th wheel builds will work well with all sorts of odds and sods - Ardents, Bards, and Factotums, and Human Paragons/Exemplars all fulfil such roles really quite well. You can optimize any in one particular direction that your party needs, but also have a host of other tricks - such as Combat (Dragonfire Inspiration, Metamorphosis, Iaijutsu Focus/Sneak Attacking etc), Party Facing (through skills, and enchantment spells/powers), or just general aid (Inspiration, Psionic Minor Creation, and decent skill lists).
Others include Divinations/Knowledge Oracle type builds, dedicated crafters (especially in a strictly random wealth game), and in lower level/low magic games, survival and movement experts - a mountain climbing/jumping/tumbling type character can help a party get places that otherwise require magic to get to, while food gathering for a party to get provisions is a must.
