Nesting aids for birds

Since Valentine's Day, it's all been about bird love.  We made bird shaped biscuits which we were going to hang on a branch in pairs although the biscuits never made it to the branch...  We set up a diamond shaped nesting box for robins in a spot hidden amongst a dense wall climber which has been a popular spot for nesting in past seasons and we have also been hanging out bits of wool for the birds to take to line their nests.  At dawn each morning, it warms my heart to listen to the increased amount of bird song heralding in spring.