There are many interesting ecological relationships between nesting weavers and other organisms. Weavers often breed in association with larger birds or with wasps, or long-lasting weaver nests may be taken over by other birds or mammals. Read more about some of these associations:

• nest association with wasps;
• nest association with waterbirds;
• nest association with birds of prey, eg kites, Sakalava weaver nesting with raptors;
• weaver nest used as platform for nest of other species, eg Verreaux's Eagle;
• weaver nests taken over by other species, see several examples, Sociable Weaver examples, Pygmy Falcons, Climbing Mouse.

Addendum: is there an association between social spiders and sparrow-weavers?