As information technology supports more aspects of modern life, digital access has become an important tool for developing regions to lift themselves from poverty. Though broadband internet connectivity will not be universally available in the short-term, widely-employed mobile devices coupled with novel delay-tolerant networking do allow limited forms of connectivity. This paper explores the design space for internet access systems operating with constrained connectivity. Our starting point is C-LINK, a collaborative caching system that enhances the performance of interactive web access over DTN and cellular connectivity. We discuss our experiences and results from deploying C-LINK in Nicaragua, before moving on to a broader design study of other issues that further influence operation. We consider the impact of (i) storing web content collaboratively cached across all user nodes, (ii) hybrid transport layers exploiting the best attributes of limited cellular and DTN-style connectivity. We also explore the behavior of future systems under a range of usage and mobility scenarios. Even under adverse conditions, our techniques can improve average service latency for page requests by a factor of 2X. Our results point to the considerable power of leveraging user mobility and collaboration in providing very-low-infrastructure internet access to developing regions.