You might have spotted that I’ve started stocking a selection of fold-over elastic in a few different widths.
FOE makes super-comfie undies, but it can also be used for other sewing projects!
Bras and Bralettes

Cartesian Crop from Sophie Hines is available up to 127cm bust

The Black Beauty Bra from Emerald Erin is available up to a 40G

The Banksia Bralette from Muna and Broad is available from a 97-162cm bust

The Fierce Bra from Pattern 4 Pirates is available up to a 154.2cm bust and also comes in child sizes.
Eye masks & accessories

Dyadic Eyemask from Sophie Hines uses fold-over elastic but makes the straps customisable!

The Ultimate Sleep Mask from Ohhh Lulu Lingerie uses fold-over elastic for a comfortable strap.

Velo Knit Run Bike Cap from The Last Stitch is perhaps not especially seasonal for us here in NZ right now, but might be good for cycling on chilly mornings
Camisoles & Singlets

The pattern bonus of the Julia Tank from Seamwork makes straps from fold-over elastic. The Julia is available up to a 137cm bust and 147cm hip
The Go Shorties & Cami from Madeit Patterns is available up to a 112cm bust and 120cm hip
The Tropo Camisole from Tuesday Stitches is available up to a 132cm high bust and 139.5cm hip

The Wonder Unders from Scroop Patterns bundles up an undies and camisole pattern, which is available up to 112cm bust and 137.5cm hip
Undies

The Ava High-Waisted Panties from Ohhh Lulu Lingerie are available up to a 112cm hip

The Kapunda Undies from Muna and Broad are available from a 105-182cm hip

The Median Knickers from Sophie Hines is available up to a 144cm hip

The super basic underpants from Halfmoon Atelier is available up to a 170cm hip

The Waratah Undies and Period Undies from Muna and Broad is available from a 105-182cm hip

Arccoss Undies from Sophie Hines are available up to 134cm hip
Other project ideas
You can also use fold-over elastic for swimwear (especially if you mostly swim at the beach), and for no-sew projects like hair ties. Fold-over elastic can also be used for homemade face-masks!