Solutions: Open Science Data Cloud
This article about Bionimbus, about an effort to efficiently and securely share cancer genomics data, mentions the Open Science Data Cloud. The OSDC is a platform for sharing large datasets, and although their current set of projects, including Bionimbus, are mostly genomics-focused, they seem to be open to datasets of all types.
From the article:
Megan McNerney, an instructor of pathology at the University of Chicago, used Bionimbus to analyze data that led to her discovery that gene CUX1, which acts as a tumor suppressor, is frequently inactivated in acute myeloid leukemia.
"Bionimbus was critical for my work, as it was used for all aspects of the project, including secure storage of protected data, quality control of next-generation sequencing results, alignments, expression analysis, and algorithm development," she said. "The strength of Bionimbus, however, is the support that is provided for end users, which enabled both expert and non-expert team members to use the cloud."
This seems very useful, as one of the primary objections to open sharing of data is security. Not that these projects are completely open - and it's not clear how one gets access, and how much these will be used to enable already existing small collaborations vs more "crowd-sourced" projects - but it's a proof of concept, at least.
Although their raison d'être seems to be secure data, they also host a small number of public data sets.