[SpecialK]

This is a budget-priced zoom that produces generally good images, but a bit soft around 300mm. It has a macro switch to allow close focusing in the 200-300mm range. Fairly lightweight though a bit bulky, when at 300mm and close focused, the length is over 10", so you can't really be inconspicuous. Note there are a couple versions of the lens, and supposedly the APO version is the only "good" one.

Here are some samples.