MySociety built the No 10 Petitions website
A DIY guide to becoming an MP and a database of the connections between the powerful could soon be created online.
The two ideas are among those being considered by MySociety - a charitable group that helps construct civic tools.
It is looking for ideas for new ideas to enhance its existing sites, entirely new projects or ways to spread the word about the digital democracy group.
Previous competitions have produced a site that automated and logged Freedom of Information (FOI) requests.
Statistics from the Ministry of Justice suggest that the FOI site, WhatDoTheyKnow, is behind 8.5% of the requests received by central government departments.
MySociety also set up the WriteToThem website that helps people get in touch with their MP.
Similar requests for proposals were run in 2003 and 2006 and this time, said MySociety founder Tom Steinberg, it was looking for one big idea to develop.
"The next step will be on a different scale from what we have built before," said Mr Steinberg, "something that might have an order of magnitude more impact or more users."
Those submitting ideas do not need to provide detailed technical specifications, said Mr Steinberg, but the proposal must be possible to build.
All the ideas submitted will be subject to public scrutiny said Mr Steinberg. The comments will help decide which one to build. The judging panel will be comprised of the 30 or so people who keep MySociety and its associated websites running.
Those with good ideas have until 15 September to submit them to MySociety. Early suggestions include Me MP, which would make it easier to stand as an independent in a election, and LittleSis which would plot the social relationships between those in power.
Mr Steinberg said he expected recent events, both political and technological, to influence the ideas sent in.
"We are seeing a world that's being more informed by the existence of social networks," he said.
"We're also in a post MPs' expenses era when transparency has gone, temporarily, from being only of theoretical interest to literally the most contentious issue of the moment."