Cloud-based visual tool to perform NLP on text corpora

I have some text corpora to share with non-programming clients (~50K documents, ~100M tokens) who would like to perform operations like regex searches, co-locations, Named-entity recognition, and word clusters. The tool AntConc is nice and can do some of these things, but comes with severe size limitations, and crashes on these corpora even on powerful machines.

What cloud-based tools with a web interface would you recommend for this kind of task? Is there an open-source tool or a cloud service at a reasonable cost ($1,000 for the volume of data indicated above)?