You know, I REALLY hate Op Shops - got dragged around them ALL today by the wife looking for retro dresses to do a specific pregnancy photo shoot we/she has in mind. For once, it turned out RIGHT for me too.
First stop was Lifeline. Looked in the books - nothing I wanted. Looked in the electrical and computer stuff, and I spied something interesting. Pulled it out - one Manfrotto monopod. Looked it over - quick release fine, extension fine, head screw fine. Held onto it TIGHTLY - another guy even asked if I was definitely buying it! I paid $8.50... for a Manfrotto professional monopod
Next was the Salvation Army. There were 5 pairs of Auscam pants, and 7 pairs of Auscam blouses/shirts. All medium / Cadet size,all genuine Auscam. $5 each! Bought the lot for my mate who runs the Army Cadets out near Maidenwell, seeing the government is too damned stingy to supply them. There was also a genuine pair of current issue army boots in my size - grabbed them at $12. Then, the surprise was the Soviet Army belt with buckle on the rack - they gave me it free

And, in the book section, they had a copy of Charles Darby's "RNZAF: the first decade 1937-46" for the grand sum of $4 - a book I had been looking for to compliment my Pentland books on the RAAF in WW2 for around 20 years!!!
Wife ended up spending $60, with me about the same

All for good causes.
Alas, not a single bit of astro gear except for a WAY over-priced Celestron Powerseeker.