Actually a forum topic that had to do with "zone pushing" and or "micro climates" could be very helpful. Anyone else think so?

I do think so! Techinically there is a tropicalsque fourm on this site, but its not very active. But anyways heres the list of what Im growing outside year round thats considered tropical-ish

Palms first...
windmill palms (2 have survived 1 winter in the ground and one is newly planted in shade)

sabal minor (survived 1 year in the ground and growing about 2-4 new leaves a year

pindo palm (survivied 1 year in the ground and still has yet to push out a full new leaf, but no winter damage or spear pull)

Medditeranean fan palm (Newly planted this spring. It already has a pup growing and is a pretty good grower)

Livingstonia chinesis (Newly planted this spring. Slow growth but it has pushed 1 full leaf this spring)

Sabal Domingensis (Newly planted this spring as well. Its pretty large but not very cold tolerant so we shall see)

I did want to try a hardy bamboo palm but it got spear pull so now I will have to replace it with another exotic and somewhat cold tolerant palm for shade (since thats the spot I want to fill)

So now onto the non-palm tropicals
Camellia (at least 10 years in the ground. Its a slow grower but has never recieved protection, is not a super cold tolerant cultivator, and blooms every year (some years better than others). It is a slow growers and does get burned leaves some years.

Spanish moss (only tried a little pieve of it on my tree this past winter and at least half surivived fine).

Cast Iron plant (just planted a week ago, some in pots, some in the ground. We shall see how they do!)

Easter lily (I left the bulbs on the deck all winter long exposed to the cold and they were still fine when spring came. I think some of it rotted when I planted it in the ground but it has plenty of offspring comming up. Also its definitely an easter lily and not some other type of lily.)

Sago palm (It does go inside from mid december to early march, but its the last potted plant to go in so I think it deserves to be on my list. It handles frost with no problems at all).

Frost proof gardenia (First year in the ground. Its not in the greatest spot but I think it has blooms comming up already so Its a strong plant. My tropical gardenia also is blooming but it goes inside in the winter)

Cordyline australis (Kind of marginal here but they always do fine in the unheated garage. They usually are alrigt outside too if kept away from moisture. I have seen some survive 2 or 3 winters in a row and get pretty tall before dieing from a cold year).

Eastern prickly pear (Not very tropical but it is rarer here even though it is native to the area. It survived in a pot evern though some of the pads didnt have roots yet. Now they all have firm roots and some have flower buds and at the least new pads).

Thats about It I can think of off the top of my head. I have seen many other subtropical plants around the area and many of them are thriving (and most are very reliable in a zone 7). I plan on trying even more things out in the future but most of my plants are tropical and in pots.

Good luck!

Hi
Since I'm in zone 10 I push zones the other way trying to grow plants that require cold dry or cool rest periods .lol Formost are iris and CPS.roses
Gardeners are never happy!!! gary

Gary, just remember, roses are not without their problems in the North either. Some of mine are having problems this year. On the other hand, I've had Floridians ask why my palms look healthier than theirs (one reason may be lack of palm specific pests and blights in the North and other areas outside their native range).

But to return to the OP's question, aside from palms (Trachycarpus,Pindo, Needles, and Chamaerops),I also grow the following subtropicals outside:

Magnolia grandiflora (several cultivars)
Loquat (Eriobotra japonica)
Podocarpus
Bamboo (clustering and spreaders)
Sweet Olive (Osmanthus)
hardy cactus and succulents
Yuccas
Basjoo bananas
Spanish moss (Tillandsia)
Fatsia japonica
Yaopon holly (I. vomitoria)
Rosemary
Lemon Verbena
Figs
Hardy Orange (Poncirus)
Bay trees (Laurel nobilis)
Live Oak (Quercus virginiana)
Bald Cypress
Photina "Red Tip"

May try experimenting with one of my containerized olive trees one of these years.

Happy Gardening!

Here is what I am growing

Palms:

4 windmill palms 2 of which which already survived one winter

1 big sabal minor
2 seedling sabal Louisiana
2 seedling pindo palms
1 Majesty palm already strarting to trunck (indoors over winter)
1 small majesty palm
1 Chamaedorea elegans

Bannanas:

musa basjoo
musa siam ruby
musa rojo

Canna:
Lots of these cultivars
pretoria
musofolia grande
indica purpurea
red king humbert
the president

castor beans

elephant ears

xanthomos lime zinger

variegated shell ginger

basket plant

meyer lemon
ponsirus orange

3 types of opuntia cactus

ice plant

agave montana

giant variegated reed

cordyline austalias green and red

yucca recurvefolia and alofolia and glorisa