While weblogs have been conceptualised as personal thinking spaces since their early days, those uses have not been studied in detail. The purpose of this paper is to explore how a weblog can contribute to the process of developing ideas in a long-term complex project. To do so I use autoethnography to reconstruct my personal blogging practices in relation to developing PhD ideas from two perspectives. I first discuss my practices of using a weblog as a personal information management tool and then analyse its uses at different stages in the process of working on a PhD dissertation: dealing with fuzzy insights, sense-making and turning ideas into a dissertation text. The findings illustrate that next to supporting thinking in a way private notebooks do, a weblog might serve similar roles as papers on one's office desk: dealing with emerging insights and difficult to categorise ideas, while at the same time creating opportunities for accidental feedback and impressing those who dr...