Here are a few of my wants, though I like almost anything unusual:
Abutilons (flowering maples) with double or striped blooms
Anemones hardy to zone 5
Calceolarias other than yellow
Calendula 'Kinglet,' 'Sunset Buff,' 'Victoria Sunset'
Camellias
Chiritas (AKA primulinas) except tamiana
Corydalis, blue-flowered types, fresh seed
Cyclamens (hardy and houseplant types)
Delphinium 'Chocolate,' 'La Boheme,' 'Green Twist,' 'Phantom'
Dianthus (pinks), heirloom and unusual
Erodiums
Fuchsias
Gardenias
Gentians
(Hardy) Geraniums with dark-centered, double, or veined blooms
Gerberas (seeds kept refrigerated)
Helianthus (sunflowers) with double, semi-double, or dark flowers
Hepaticas
Jasmines
Justicias
Lisianthus (AKA eustomas)
Osteospermum 'Copper Purple,' 'Pink Whirls,' 'Whirligig'
Pansies, ruffled varieties, fresh seed
Passifloras (passionflowers)
Pavonia gledhillii , hirticalyx, multiflora
Primroses
Rudbeckia 'Aslan,' 'Goldquelle,' 'Radiance'
Solanum muricatum, welandii
Streptocarpus (cape primroses)
Other unusual flowers, herbs, or tropicals