I invest in a small number of early stage companies each year and work directly with teams, usually on product design, technical architecture, engineering recruitment and management coaching. I've occasionally gotten into mocks and code. And sometimes had opportunities to help with business development and M&A/corpdev activity.
Prior investment wins include:
Slideshare, Khush Labs, PageLever, GroupCard, Togetherville
I'll try to syndicate every investment I make, though it's up to each company to accept syndication or not.