- **GDS layout tools**: klayout is the go-to viewer for GDS files; GDS3D (sourceforge & github.com/skuep/GDS3D) adds 3-D visualization; GDS2WebGL (github.com/s-holst/GDS2WebGL) offers browser viewing but lacks orthographic projection, making it unsuitable for precise design-rule checking.

- **Hashcash post-mortem**: The original hashcash anti-spam proposal (hashcash.org/docs/hashcash.html) was never adopted; discussion centered on why a local double-spend database is impractical (O(N²) server-to-server gossip) and how embedding only the recipient address in the PoW could have simplified the scheme.

- **Spam economics vs. PoW**: Participants argued that hashcash fails because attackers can rent cheap VPS or botnet cycles while legitimate users on battery-powered devices bear disproportionate cost; the conversation pivoted to privileging pre-existing relationships (e.g., Tox’s rotating contact addresses) over proof-of-work.

- **Bone-marrow misconception corrected**: kanzure discovered that marrow donation does not require direct intra-bone injection; cells are simply infused intravenously and home to marrow cavities on their own.

- **Longevity statistics caution**: L29Ah linked Gwern’s critique (gwern.net/Longevity#metformin) of naïve metformin life-extension calculations, illustrating how improper utility models can mislead intervention assessments.