I think it's about time we brought back extensive link pages, since it's increasingly impossible to find the quality stuff that's still out there on the internet!
Friends
Rachel L. Cohen Illustration and Design - Very cool trad tattoo styling and sports designs
Mel Pool Cosplay and Gaming - Great cosplay and streaming
Silver Alicorn - Music, fonts, red pandas
Orbital Dawn-Cool videogame project by the previous
Triumphant Bass - Cosplay, streaming
MilkTooth Co - Extremely cute printmaking and bits and bobs from KZ
Burgundy Comics - CJ's Comic's page
Dangerous Ladies - All the bits and bobs and props and fabrics for your cosplays
Materials/Shops
**I have no affiliation with any of these shops, but sometimes it can be hard to find where to buy things!*
WAWAK - For all your sewing notion needs
Lisa Sorrell Notions - Boot and shoe making supplies
Sew Sassy - Swim/lingerie fabrics notions and elastics.
McClain's Printmaking - Lino and woodcut supplies
Tutorials
Images/Resources
Internet Archive Favorites - What it says--lots of books I use for image reference.
Philadephia Museum of Art Collection Search - PMA Collection
The Met Collection - The Metropolitan Museum of Art Collection
LiveAuctioneers - Lots of mid-range art and antiques, I use for references a lot
Auctionet - Similar to above, but European
The Morgan Library and Museum - Lots of prints, drawings and manuscripts
Abecedarin - I don't really know how to describe this one, but there's interesting stuff, mostly from early print sources
Artsy - Contemporary art in galleries now
TFAO - Crunchy old site, but if you were ever looking to learn more about a lesser-known, local American artist, they might have information
Science Fiction Ruminations - Great blog on vintage sci-fi art and writing
The Commercial Pattern Archive - Database of historical and modern sewing patterns.
Larsdatter - A list of links to images and resources for various categories of Medieval material culture
Res Rarae - Really neat gallery of reproductions of shoes from ancient times up to 19th century
Old Internet
Diabella's Vintage Cat Graphics - Amazing site full of cat gifs
Scri8e - Lots of gems, moons, and star gifs
Veggie Studio - Dress up games!
Philadelphia Area
InLiquid - Gallery and artist community, they also post lots of artist opportunities and calls for entry
Philadephia Cultural Alliance Job Bank - For listing and finding jobs in and around the arts