It's great to see all the new approaches in this field. IMHO animated interactive visualization of the current flow is pretty to look at, but beyond a certain e

It's great to see all the new approaches in this field. IMHO animated interactive visualization of the current flow is pretty to look at, but beyond a certain early point in one's understanding of voltage & current relationships, it's not necessarily more useful than not being there at all (and having non-interactive access only). For a CS analogy: when you're trying to teach how and why to balance a binary search tree, it's useful to visually draw out the trees of the first few example steps. However, after you understand the concepts and the invariants, it would be rather unhelpful (or even distracting) to have an animated drawing of the tree as the algorithm progresses every time you were working with a BST! Disclosure -- I wrote CircuitLab https://www.circuitlab.com/ https://www.circuitlab.com/ -- another browser-based circuit simulator and schematic capture tool which doesn't do animated graphs, but instead includes: * algebraically-defined behavioral sources (the ability to define voltage/current relations as an expression, like a spreadsheet or programming language) * extended-precision numerical core (simulates circuits that make SPICE variants choke) http://www.edn.com/design/analog/4418707/1/Extended-precision-simulation-cures-SPICE-convergence-problems http://www.edn.com/design/analog/4418707/1/Extended-precisio... * frequency-domain analysis (Bode plots) * parametric simulation sweeps over any parameter in any element * export publication-quality vector PDF/EPS/SVG and raster PNGs of your schematics * easily add custom elements with pins to represent any stuff you like (connectors, modules, etc) * pure JS solution, or more specifically, CoffeeScript compiled to JS -- the creator of CoffeeScript said "an order of magnitude more [lines of code] than I've ever dealt with in a single project" https://news.ycombinator.com/item?id=3644662 https://news.ycombinator.com/item?id=3644662 (and the LOC count has grown substantially since that comment!)