Couchbase Full Text Search (FTS) can be used to index and query geospatial data, even without a dedicated spatial database. A use case example demonstrates how to create an FTS index on a sample dataset of cities and towns, and then run various geospatial queries against the index using different methods such as point and radius, bounding box, and polygon searches. These searches can be used to find locations within a certain distance or area from a specific point, and the results can be sorted by various fields such as population, elevation, or name. The example also highlights the flexibility of Couchbase FTS in handling different types of geospatial data and queries, making it a useful tool for applications that require geospatial search capabilities.